Polychaete Worms of the Genus Perinereis (Annelida, Nereididae) from Taiwan, with Description of 17 New Species

© 2024 Academia Sinica, Taiwan Open Access Polychaete Worms of the Genus Perinereis (Annelida, Nereididae) from Taiwan, with Description of 17 New Species Pan-Wen Hsueh* Department of Life Sciences, National Chung Hsing University, 145 Xingda Rd., Taichung city 402, Taiwan. *Correspondence: E-mail: [email protected] (Hsueh) urn:lsid:zoobank.org:pub:24B016F7-CC24-4653-AA92-0A826E8F3B20 Received 2 August 2023 / Accepted 19 July 2023 / Published 27 December 2024 Communicated by Benny K.K. Chan A taxonomic review on the genus Perinereis (Annelida, Polychaeta, Nereididae) from Taiwan has been conducted by examining over 1000 specimens of the worms in the author’s private collection and in the depository of the National Museum of Natural Science. A total of 24 species for this genus has been recognized in the present study. Of these 24 species, 17 are new to science, and they are: Perinereis daxiensis sp. nov., P. fugangensis sp. nov., P. kaomeiensis sp. nov., P. kebalanae sp. nov., P. houbihuensis sp. nov., P. hsinchuensis sp. nov., P. liuqiuensis sp. nov., P. longdongwanensis sp. nov., P. ludaoensis sp. nov., P. pangcahae sp. nov., P. pseudocultrifera sp. nov., P. qiguensis sp. nov., P. taitungensis sp. nov., P. tubicola sp. nov., P. wanlitongensis sp. nov., P. yehliuensis sp. nov., and P. yufuensis sp. nov. The presence of P. cultrifera (Grube, 1840) in Taiwan is confirmed. The remaining six are species previously reported from Taiwan, which are: Perinereis aibuhitensis (Grube, 1878), P. floridana (Ehlers, 1868), P. mictodonta (Marenzeller, 1879), P. nigropunctata (Horst, 1889), P. vancaurica (Ehlers, 1868), and P. wilsoni Glasby & Hsieh, 2006. The generic diagnosis is partially amended to include the presence of neuropodial homogomph spinigers found in the subacicular fascicle of P. longdongwanensis sp. nov. A key to Perinereis species reported from Taiwan is herein provided. Key words: Biodiversity, Perinereis polychaetes, Nereidinae, Taxonomy, Taiwanese waters BACKGROUND The genus Perinereis Kinberg, 1865 is characterized by having conical and bar-shaped paragnaths on area VI of the pharynx and is one of highly diversified nereidid with 92 recognized species worldwide (Bakken et al. 2018). Several regional taxonomic revisions of the genus in the West Pacific are available: For instance, Grube (1878; Philippines), Wu (1967; Taiwan), Imajima (1972; Japan), Wu et al. (1981 1985; China), Hutchings et al. (1991; Australia), Sun and Yang (2004: China). Other taxonomic revisions were emphasized on the single species complex (like the nuntia species complex) of the genus (Wilson and Glasby 1993; Glasby and Hsieh 2006). For convenient studying this highly diversified taxon group, Hutchings et al. (1991) proposed a grouping system by breaking down these species into nine categories based on the number of bar-shaped paragnaths on area VI of the pharynx and the degree of expansion of notopodial dorsal ligule on posterior chaetigers, and these categories are: G1A, G1B and G1 with unknown condition of notopodial dorsal ligule, G2A, G2B and G2 with unknown condition of notopodial dorsal ligule, and G3A, G3B and G3 with unknown condition of notopodial dorsal ligule, whereas A and B represent conditions of notopodial dorsal ligule on posterior chaetigers are not greatly expanded and greatly expanded, respectively. Citation: Hsueh PW. 2024. Polychaete worms of the genus Perinereis (Annelida, Nereididae) from Taiwan, with description of 17 new species. Zool Stud 63:39. doi:10.6620/ZS.2024.63-39. Zoological Studies 63:39 (2024) doi:10.6620/ZS.2024.63-39 1 © 2024 Academia Sinica, Taiwan Wu (1967) reported 10 Perinereis species from Taiwan, but four of them are considered junior names of the other species by latter works, which are: P. novaehollandiae Kinberg, 1865, P. cultrifera (Grube, 1840), P. linea (Treadwell, 1936), and P. brevicirris (Grube, 1866). Hutchings et al. (1991) synonymized P. novaehollandiae with senior name of P. amblyodonta (Schmarda, 1861); Park and Kim (2017) considered P. cultrifera as a new species of P. euiini Park and Kim, 2017; Imajima (1972) synonymized P. linea as junior name of P. vancaurica tetradentata Imajima, 1972, but Hutchings et al. (1991) later synonymized these two species as junior names of P. vancaurica (Ehlers, 1868); Glasby and Hsieh (2006) commented that material of P. brevicirris examined in Wu (1967) was actually represented by three different species, P. mictodonta (Marenzeller, 1879), P. shikueii Glasby and Hsieh, 2006, and P. wilsoni Glasby and Hsieh, 2006. The total number of Perinereis species reported from Taiwan was increased to only 12 with latter studies of Chen et al. (2002) and Glasby and Hsieh (2006), which are: Perinereis aibuhitensis (Grube, 1878), P. amblyodonta, P. euiini, P. floridana (Ehlers, 1868), P. helleri (Grube, 1878), P. mictodonta, P. neocaledonica Pruvot, 1930, P. nigropunctata (Horst, 1889), P. shikueii, P. singaporiensis (Grube, 1878), P. vancaurica, and P. wilsoni. Villalobos-Guerrero et al. (2021: 3, fig. 1A– C) redefined the terminology for conical paragnaths as “broad-petite bar-shaped” paragnaths and transferred Neanthes babuzai Hsueh, 2019, N. kinmenensis Hsueh, 2019 and N. shigungensis Hsueh, 2019 to Perinereis by claiming all three species have bar-shaped paragnaths on area VI of the pharynx. However, this newly proposed classification to call conical appearance paragnaths as “broad-petite” bar-shaped paragnaths is considered premature (C. Glasby, pers. comm.). The author herein regards these new combinations as requiring verification. Hsueh (2018 2019a b 2020 2021 2022) reported a total of 28 new species, new record genera and new record species of several nereidid genera (i.e., Composetia Hartmann-Schröder, 1985, Eunereis Malmgren, 1865, Dendronereis Peters, 1854, Neanthes Kinberg, 1865, Nereis Linnaeus, 1758, Platynereis Kinberg, 1865, and Pseudonereis Kinberg, 1865) from Taiwan. These reports suggest that biodiversity of Perinereis Kinberg, 1865, one of most diversified nereidid genera, in this geographic region might also be overlooked. Consequently, the author examines Perinereis specimens of his private collection, cumulated from over three decades of field samplings along Taiwan and in the depository of the National Museum of Natural Science, Republic of China, in the present study to increase understanding on biodiversity of this genus occurring in Taiwan. As results, a total of 24 species for the genus has been recognized. Of these 24 species, 17 species are new to science, one occurrence reconfirmed species, and six previously reported species. The present study describes these 17 new species and reports the presence of seven previous recorded species. Of these 17 newly described species, P. longdongwanensis sp. nov. possess homogomph spinigers in the subacicular fascicle of neuropodia, which is not included in the generic diagnosis. Therefore, the generic diagnosis is herein partially emended. A key to Perinereis species reported from Taiwan is also provided. MATERIALS AND METHODS Some 1000+ specimens were examined in the present study. These specimens were collected from hard or soft bottoms of intertidal habitats in Taiwan and vicinity offshore islands during various ecological surveys in the past 30 years (Fig. 1). These collections were made using shovels, chisels, and hammers where it applies. All specimens were relaxed with menthol before fixed with 10% buffered formalin and later transferred to 70% alcohol for storage. They were later examined using stereo (Leica MZ12.5) and compound microscopes (Leica DM2500). Digital images of body parts of these animals were taken with Canon EOS 6D Mark II, 26.2 megapixels and Canon EOS 7D Mark II, 20 megapixels. When it is necessary, photo images were processed with computer software Helicon Focus 7.0.2 and PhotoImpact 8 to enhance photo sharpness. Figures were prepared using CorelDraw 5 Suite X. Terminology of prostomium region and chaetal morphology followed Bakken and Wilson (2005); description of parapodia followed Villalobos-Guerrero and Bakken (2018); description of paragnath patterns and areas VII–VIII in furrow-ridge regions followed Conde-Vela (2018); and description of ridge pattern of areas VI–V–VI followed Villalobos-Guerrero (2019). The tentacular belt was used to describe the anterior apodous segment of the worm (Salazar-Vallejo et al. 2021). Length measurements of dorsal ligule and dorsal cirrus followed Conde-Vela (2018: 257, fig. 6C–F). A symbol “x” is used to express multiples. Abbreviations: IRHB = intertidal rocky hard bottom; SRHB = subtidal rocky hard bottom; ISSB = intertidal soft sediment bottom. All specimens of this study were deposited at the National Museum of Natural Science (NMNS), Taichung, Taiwan, Republic of China. The name of specimen collector was showed only of which the specimen is not collected by the author. Numbers in parentheses represent variations of a given morphological character. page 2 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan RESULTS TAXONOMY Family Nereididae Blainville, 1818 Subfamily Nereidinae Blainville, 1818 Genus Perinereis Kinberg, 1865 Type-species: Perinereis novaehollandiae Kinberg, 1865 by subsequent designation. Diagnosis (after Glasby 2015: 226, new feature highlighted in boldface): Frontal antennae present, 1 pair. Palpophore with transverse groove present; palpostyles conical. Prostomium with entire anterior margin. Eyes present, 2 pairs. One apodous anterior segment, greater than length of chaetiger 1. Tentacular cirri with distinct cirrophores. Jaws with smooth or slightly crenulate cutting edge or with dentate cutting edge. Maxillary ring of pharynx with paragnaths, Oral ring paragnaths present. Dorsal notopodial ligule present. Prechaetal notopodial lobe present or absent. Ventral notopodial ligule present. Dorsal cirrus simple, Fig. 1. Collection sites of the present study. N page 3 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan lacking basal cirrophore. Neuropodial prechaetal lobe absent. Neuropodial postchaetal lobe absent or present. Ventral neuropodial ligule of anterior chaetigers present. Ventral cirri single. Notoaciculae absent from segments 1 and 2. Notochaetae are homogomph spinigers. Neurochaetae dorsally are homogomph spinigers, heterogomph falcigers; blades serrated. Neurochaetae ventrally homogomph spinigers (may be absent), heterogomph spinigers (may be absent), heterogomph falcigers; blade lacking distinct tendon on terminal tooth. Anal cirri cirriform or conical. Perinereis aibuhitensis (Grube, 1878) (Fig. 2) Nereis (Perinereis) aibuhitensis Grube 1878: 89–90, p1. 5, fig. 3; Horst 1924: 168–169, p1. 33, figs. 4–6. Nereis aibuhitensis Monro 1934: 361–362. Neanthes linea Treadwell 1936: 268–270, fig. 19a–e. Neanthes orientalis Treadwell 1936: 270–272, fig. 19f–i. Perinereis aibuhitensis Fauvel 1932: 106, 1953: 209–210, fig. 107a; Russell 1962: 6–7; Wu 1967: 70; Wu et al. 1981: 171–172, figs. 107A–J, 108A–H, 109A–F; Wu et al. 1985: 189–193; Hylleberg et al. 1986: 3–5, fig. 2A–Q; Hutchings et al. 1991: 245–246, fig. 2a–e. Material examined: Changhua County: 1 specimen, NMNS 8748-1, Xigung (23°52.29'N, 120°17.60'E), habitat type: ISSB, 17 March 2007; 1 specimen, NMNS 8748-2, Fubao (24°02.83'N, 120°22.75'E), habitat type: ISSB, 18 March 2007; 1 specimen, NMNS 8748-3, Fubao Bridge (24°02.68'N, 120°22.91'E), habitat type: ISSB, 18 March 2007; 3 specimens, NMNS 8748-4–6, Fubao Bridge (24°02.69'N, 120°22.90'E), habitat type: ISSB, 1 May 2007; 1 specimen, NMNS 8748-7, Zhuoshui (23°51.50'N, 120°22.75'E), habitat type: ISSB, 20 March 2009; 1 specimen, NMNS 8748-8, Zhuoshui (23°51.50'N, 120°22.75'E), habitat type: ISSB, 7 June 2010; 1 specimen, NMNS 8748-9, Xianxi (24°05.17'N, 120°25.13'E), habitat type: ISSB, 22 April 2017. Chiayi County: 1 specimen, NMNS 8748-10, Bazang (23°19.51'N, 120°07.78'E), habitat type: ISSB, 7 January 2007. Description: Based on five complete specimens (NMNS 8748-1, 4, 6, 8,10; all atoke) and five incomplete specimens (NMNS 8748-2–3, 5, 7, 9; all atoke); complete specimens for general body morphology, incomplete specimens for anterior body morphology and paragnath pattern only: Body length 75.0–179.0 (n = 5) mm with 152–202 (n = 5) chaetigers, chaetiger 10 width 1.0–5.0 (n = 10) mm, excluding parapodia; beige in alcohol (Fig. 2A, B). Prostomium wider than long, lateral antennae antero-lateral, shorter than palps, palpophores globose, palpostyles spheroid. Four pairs of tentacular cirri, longest one reaching chaetiger 2–6 (n = 10). Two pairs of eyes, in trapezoidal arrangement. Tentacular belt about 1.1–1.4x (n = 10) longer than chaetiger 1. Pharynx with dark brown jaws, each with 5–7 (n = 10) teeth; paragnath pattern: I = 3–6 (mostly 4 or 5, one case of 3 and 6; n = 10, same sample size on following areas), in triangle or cluster; II = 12–23 (left), 11–26 ones (right), in 2–3 oblique rows; III = 40–57 (center region with 27–56 cones, in 3–4 transverse rows; mostly 2 lateral regions, each with 0–3 or 0–4 cones; one case of 4 lateral regions, outer lateral regions with 2 cones, inner lateral regions with 6 or 8 cones, in longitudinal lines); IV = 14–25 (left), 15–23 (right), in 2–3 oblique rows; V = 3, in triangle; VI = mostly 2 short bars, one case of 1 additional cone (left), mostly 2 short bars, one case of 3 short bars (right), in transverse row; VII–VIII = 39–58, in 3–4 rows. Ridge pattern of areas VI–V–VI, u-shaped (Fig. 2A, B). Dorsal cirri digitiform, medially attached to dorsal ligule on anterior to mid-body chaetigers, about 0.4–0.5x as long as dorsal ligule, attached 1/3 to base of dorsal ligule on posterior chaetigers, about 0.2x as long as dorsal ligule (Fig. 2C–E). Dorsal ligule subconical throughout, about 1.8x longer than median ligule on anterior chaetigers, about 2.0–2.2x longer than median ligule on mid-body to posterior chaetigers; center lobe of dorsal ligule with one irregular-shaped glandular mass on posterior chaetigers (Fig. 2E). Notopodial prechaetal lobe absent. Median ligule subconical throughout, as long as neuroacicular ligule on anterior and posterior chaetigers, greatly longer than neuroacicular ligule on mid-body chaetigers (Fig. 2C–E). Neuroacicular ligule with predominant inferior lobe on anterior chaetigers, about 0.4–0.5x as long as ventral ligule, inferior and superior lobes subequal in length on mid-body to posterior chaetigers, about 0.5x as long as ventral ligule on mid-body chaetigers, about 1.5x longer than ventral ligule on posterior chaetigers. Neuropodial postchaetal lobe absent. Ventral ligule subconical throughout. Ventral cirri digitiform, midventrally attached to ventral edge of parapodia, as long as ventral ligule throughout (Fig. 2C–E). Notochaetae present from chaetiger 3 to posterior chaetigers, homogomph spinigers present throughout. Supra-acicular fascicle of neuropodia: homogomph spinigers and long-bladed heterogomph falcigers with serrations present throughout. Subacicular fascicle of neuropodia: long-bladed heterogomph falcigers with serrations and heterogomph spinigers present throughout (Fig. 2F). Pygidium with anus crenulated; anal cirri cirriform, as long as last 3–8 (n = 5) chaetigers. Distribution: Australia, China, India, Andaman page 4 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan Islands, Indonesia (Sulawesi, Sumatra, Java), Philippines (Hutchings et al. 1991), Taiwan (Wu 1967). Remarks: Morphology of examined specimens in the present study largely agrees with redescription of P. aibuhitensis (Grube, 1878) in Hutchings et al. (1991: 245, fig. 2a–c) (Fig. 2A–F). However, some morphological discrepancies can be noted between present specimens and redescription: 1) several present specimens have greater number of paragnaths on areas I (up to 6 versus 4), II (mostly with 16–23 versus 6–14), III (40–57 versus 8–23); and 2) one present specimen has two short bars and one cone on left side of area VI and three short bars on left side of area VI (versus always 2 short bars on each side of area VI) (Hutchings et al. 1991: 245, fig. 2a–c). These discrepancies might be due to the size-related variations. Moreover, present specimens have one glandular mass on center lobe of dorsal ligule on posterior chaetigers (Fig. 2E), which is not mentioned by neither Wu (1967), nor Hutchings et al. (1991: 245); however, this feature had been illustrated in Hylleberg et al. (1986: 4, fig. 2E, J). This species is commonly found in soft bottom habitats of river mouths and coastal flats of western Taiwan. Perinereis cultrifera (Grube, 1840) (Fig. 3, Table 2) Nereis cultrifera Grube 1840: 76, fig. 6. Perinereis cultrifera Hutchings et al. 1991: 253–254, fig. 8a–c; Park and Kim 2017: 255, figs. 4C, 5F. Material examined: 19 specimens, NMNS 874811–20, Fuguijiao (25°17.75'N, 121°31.99'E), habitat type: IRHB, 19 November 2003; 11 specimens, NMNS 8748-21–22, Fuguijiao (25°17.75'N, 121°31.99'E), habitat type: IRHB, 12 March 2004; 16 specimens, NMNS 8748-23, Shimen (25°17.85'N, 121°34.14'E), habitat type: IRHB, 14 March 2004; 13 specimens, NMNS 8748-24–27, Shimen (25°17.85'N, 121°34.14'E), habitat type: IRHB, 17 March 2006; 10 specimens, NMNS 8748-28–32, Shimen (25°17.85'N, 121°34.14'E), habitat type: IRHB, 14–15 April 2007; 15 specimens, NMNS 8748-33–34, Wanlitong (21°59.73'N, 120°42.26'E), habitat type: IRHB, 14 December 2007; 13 specimens, NMNS 8748-35–39, Shimen (25°17.85'N, 121°34.14'E), habitat type: IRHB, 9–10 May 2008; 6 specimens, NMNS 8748-40–42, Jihuei (23°06.87'N, 121°24.21'E), habitat type: IRHB, 7–9 October 2010; Fig. 2. Perinereis aibuhitensis (Grube, 1878); A, B (NMNS 8748-9), C–F (NMNS 8748-6): A, anterior body region, dorsal view; B, anterior body region, ventral view; C, right parapodium, anterior view, chaetiger 10; D, right parapodium, anterior view, chaetiger 51; E, right parapodium, anterior view, chaetiger 101; F, neuropodial subacicular fascicle chaetae. Abbreviations: HeF = heterogomph falciger; HeS = heterogomph spiniger. Scale bars: A, B = 0.5 mm; C–E = 0.2 mm; F = 0.02 mm. page 5 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan 1 specimen, NMNS 8748-43, Jihuei (23°06.87'N, 121°24.21'E), habitat type: IRHB, 25 March 2011. Description: Based on 10 complete specimens (NMNS 8748-11–12, 14–15, 18, 24–25, 27(1); all atoke) and two incomplete specimens (NMNS 874813–17; all atoke): Body length 23.0–58.0 (n = 10) mm with 71–96 (n = 10) chaetigers, chaetiger 10 width 1.5– 3.7 (n = 12) mm, excluding parapodia; beige in alcohol Table 1. Perinereis species reported from East and Southeast Asia Taxon Type locality Distribution Habitats References P. aibuhitensis (Grube, 1878) Aibuhit (Babeldaob, Palau) Andaman Islands; Australia; China; Philippines; Taiwan A, B Wu 1967; Hutchings et al. 1991; Glasby et al. 2016 P. amblyodonta (Schmarda, 1861) New South Wales Australia; New Zealand; Philippines; Taiwan B Wu 1967; Hutchings et al. 1991; Glasby et al. 2016 P. barbara (Monro, 1926) New South Wales Australia; India; Singapore B Hutchings et al. 1991; Glasby et al. 2016 P. binongkae (Horst, 1924) Binongka, Indonesia Known only from the type locality F Horst 1924 P. brevicirris (Grube, 1866) St. Paul Island, Indian Ocean Indian Ocean; Red Sea; Persian Gulf. B, C Grube 1866; Augener 1913 P. caeruleis (Hoagland, 1920) Limbe Strait, Philippines Arabian Sea; Australia; Indonesia; New Caledonia; Southern Japan; Taiwan n.a. Wu 1967; Wilson and Glasby 1993 P. calmani (Monro, 1926) Macclesfield Bank, South China Sea Australia; China B Hutchings et al. 1991; Glasby et al. 2016 P. camiguinoides (Augener, 1922) Juan Fernandez Islands, Chile Chile; New Zealand; South China Sea n.a. Hutchings et al. 1991; Glasby et al. 2016 P. cavifrons (Ehlers, 1920) Ambon, Indonesia Indonesia; South China Sea n.a. Hutchings et al. 1991; Glasby et al. 2016 P. cultrifera (Grube, 1840) Gulf of Naples English Channel; Mediterranean; South China Sea; Taiwan B Wu 1967; Hutchings et al. 1991; Glasby et al. 2016 P. dongalae (Horst, 1924) Sulawesi, Indonesia Known only from the type locality F Horst 1924 P. euiini Park and Kim, 2017 Gusan-myeon, Korea Eastern Asia (China, Japan, Korea, Taiwan) B, D Park and Kim 2017 P. floridana (Ehlers, 1868) Florida, USA Caribbean Sea; Gulf of Mexico; Mexico B de León-González and Solís-Weiss 1998 P. helleri (Grube, 1878) Bohol, Philippines Andaman Islands; Australia; China; Indonesia; Philippines; Taiwan B, C Wu 1967; Hutchings et al. 1991; Glasby et al. 2016 P. linea (Treadwell, 1936) Xiamen, China Mediterranean; China; Korea; Taiwan C, E Treadwell 1936; Arias et al. 2013; Glasby et al. 2016 P. majungaensis Fauvel, 1921 Madagascar Madagascar; South China Sea n.a. Wilson and Glasby 1993; Glasby et al. 2016 P. malayana (Horst, 1889) Malaysia Known only from the type locality n.a. Horst 1889 P. mictodonta (Marenzeller, 1879) Japan Japan; China; Taiwan A, C, D Wilson and Glasby 1993; Glasby and Hsieh 2006 P. neocaledonica Pruvot, 1930 New Caledonia Arabian Sea; Southern Japan; New Caledonia; New Hebrides n.a. Fauvel 1932; Wilson and Glasby 1993 P. nigropunctata (Horst, 1889) Malaysia Australia; Borneo; Madagascar; Gulf of Thailand; Marshall Islands; Taiwan B, C Wu 1967; Hutchings et al. 1991; Glasby et al. 2016 P. nuntia (Lamarck, 1818) Gulf of Suez Red Sea; Gulf of Aden; tropical Indo-Pacific B, C Wilson and Glasby 1993; Glasby and Hsieh 2006 P. obfuscata (Grube, 1878) Philippines Australia; Philippines B, C Hutchings et al. 1991 P. perspicillata (Grube, 1878) Philippines Philippines; South China Sea n.a. Grube 1878; Glasby et al. 2016 P. quatrefagesi (Grube, 1878) Philippines Philippines; South China Sea n.a. Grube 1878; Glasby et al. 2016 P. rhombodonta Wu, Sun and Yang, 1981 Guangdong, China Indonesia; Malaysia; Singapore; Southern China; South China Sea; Taiwan; Thailand C Wu et al. 1981; Glasby and Hsieh 2006 P. rumphii (Horst, 1919) Banda Sea, Indonesia Banda Sea, Indonesia n.a. Horst 1919 P. shikueii Glasby and Hsieh, 2006 Taiwan Japan; Taiwan C Glasby and Hsieh 2006; Tosuji et al. 2019 P. singaporiensis (Grube, 1878) Singapore Australia; India; Indonesia; New Caledonia; Philippines; Singapore; Taiwan B Wu 1967; Hutchings et al. 1991; Glasby et al. 2016 P. striolata (Grube, 1878) Bohol, Philippines New Caledonia; Philippines; Persian Gulf n.a. Grube 1878; Pruvot 1930 P. suluana (Horst, 1924) Sulu, Philippines Australia; Malay Archipelago; New Caledonia; Papua New Guinea; Philippines D Horst 1924; Hutchings et al. 1991 P. tenuisetis (Fauvel, 1915) Port de Syracuse, Sicily Mediterranean; South China Sea F Fauvel 1915; Glasby et al. 2016 P. vancaurica (Ehlers, 1868) Nicobar Islands, Andaman Australia; tropical Indian and Pacific Oceans B, C Hutchings et al. 1991 P. viridis Glasby and Hsieh, 2006 Singapore Singapore; Sulawesi, Indonesia B Glasby and Hsieh 2006 P. weijhouensis Wu, Sun and Yang, 1981 Guangxi, China Southern China; South China Sea B Wu et al. 1981; Glasby et al. 2016 P. wilsoni Glasby and Hsieh, 2006 Taiwan China; Japan; South China Sea; South Korea; Taiwan B Glasby and Hsieh 2006 A = brackish waters; B = intertidal hard bottom; C = intertidal soft bottom; D = subtidal hard bottom; E = subtidal soft bottom; F = pelagic; n.a. = not available. page 6 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan (Fig. 3A, B). Prostomium wider than long, lateral antennae antero-lateral, shorter than palps, palpophores globose, palpostyles spheroid. Four pairs of tentacular cirri, longest one reaching chaetiger 3–8 (n = 12). Two pairs of eyes, in trapezoidal arrangement. Tentacular belt about 1.2–1.4x (n = 12) longer than chaetiger 1. Pharynx with dark brown jaws, each with 5–7 (n = 12) teeth; paragnath pattern: I = 1–6 (mostly 4–5, one case of 1, 3 and 6) (n = 12, same sample size on following areas), in cluster; II = 14–25 (left), 13–20 (right), in 2–3 oblique rows; III = 13–29 (center region with 12–24 cones, in 3–4 transverse rows; mostly 2 lateral regions, each with 1–4 or 0–3 cones); IV = 18–29 (left), 14–30 (right), in 3–4 oblique rows; V = 1–4 (mostly 3, one case of 1, 2 and 4); VI = 1 (left), 1 (right), short bars; VII–VIII = 22–37, in 2 rows. Ridge pattern of areas VI– V–VI, λ-shaped (Fig. 3A, B, Table 2). Dorsal cirri digitiform, medially attached dorsal ligule throughout, about 0.6x as long as dorsal ligule on anterior to mid-body chaetigers, about 0.4x as long as dorsal ligule on posterior chaetigers (Fig. 3C–E, Table 2). Dorsal ligule subconical throughout, about 1.4x longer than median ligule on anterior chaetigers, about 1.8–2.0x longer than median ligule on mid-body to posterior chaetigers; central and proximal lobes of dorsal ligule with one glandular mass throughout (Fig. 3C–E, Table 2). Notopodial prechaetal lobe present on anterior to anterior-most of mid-body chaetigers (Fig. 3C, D, Table 2). Median ligule subconical throughout, about as long as neuroacicular ligule throughout (Fig. 3C–E). Neuroacicular ligule with predominant inferior lobe on anterior chaetigers, about as long as ventral ligule throughout, inferior and superior lobes subequal in length on mid-body to posterior chaetigers. Neuropodial postchaetal lobe absent. Ventral ligule subconical throughout. Ventral cirri digitiform, midventrally attached to ventral edge of parapodia, about 0.7x as long as ventral ligule on anterior to mid-body chaetigers, about 0.9x as long as ventral ligule on midbody chaetigers to posterior chaetigers (Fig. 3C–E). Notochaetae present from chaetiger 3 to posterior chaetigers, homogomph spinigers present throughout. Fig. 3. Perinereis cultrifera (Grube, 1840); A, B (NSNM 8748-34(1)), C–H (NMNS 8748-28): A, anterior body region, dorsal view; B, anterior body region, ventral view; C, right parapodium, anterior view, chaetiger 10; D, right parapodium, anterior view, chaetiger 34; E, right parapodium, anterior view, chaetiger 70; F, neuropodial subacicular fascicle heterogomph falciger, chaetiger 10; G, neuropodial subacicular fascicle heterogomph spiniger, chaetiger 34; H, neuropodial subacicular fascicle heterogomph falciger, chaetiger 70. Abbreviation: NoPL = notopodial prechaetal lobe. Scale bars: A, B = 0.5 mm; C–E = 0.2 mm; F–H = 0.02 mm. page 7 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan Supra-acicular fascicle of neuropodia: homogomph spinigers and short-bladed heterogomph falcigers with serrations present throughout. Subacicular fascicle of neuropodia: short-bladed heterogomph falcigers with serrations and heterogomph spinigers present throughout (Fig. 3F–G, Table 2). Pygidium with anus crenulated; anal cirri cirriform, as long as last 2–4 (n = 6) chaetigers (Table 2). Distribution: Mediterranean Sea, English Channel (Hutchings et al. 1991); Taiwan. Remarks: Park and Kim (2017) reported that P. cultrifera reported by Izuka (1912) and Wu (1967) from Taiwan are all actually P. euiini Park and Kim, 2017. This practice makes the presence record of P. cultrifera in Taiwan no longer valid. However, material of the present study suggests that P. cultrifera does exist in Taiwan. Paragnath pattern and morphology of parapodia and chaetae of present specimens (Fig. 3B, C– G, Table 2) agree mostly with syntypes of P. cultrifera examined by Hutchings et al. (1991: 253, fig. 8a–c) and Park and Kim (2017: 255–256, 258, figs. 3A, 4A– C, 5A1, 2, 5F, table 4), including several key characters (i.e., the presence of lateral teeth on area III, central and proximal lobes of dorsal ligule with one glandular mass on all chaetigers, the presence of prechaetal lobe on anterior chaetigers, and not greatly expanded dorsal ligule on posterior chaetigers). Figure 4 in Park and Kim (2017: 255) showed that P. cultrifera has λ-shaped ridge pattern of areas VI–V–VI, which is the same as the present specimens (Fig. 3A). Nevertheless, minor morphological discrepancies between the present specimens and above-mentioned descriptions have been noted in the present study. For example, number of paragnaths on areas I and III in the present specimens have a range of 1–9 with mostly 4–5 and 13–29, respectively, whereas that of is 1–2 and 5–11 or 10–12, Table 2. Key characters of Perinereis species described in the present study of group 1A Taxon\Categories LTC TJ I IIL, IIR III/LT IVL, IVR V VIL, VIR VII–VIII RP VI–V–VI P. cultrifera (Grube, 1840) 3–8 5–7, 5–7 1–9 (mostly 4–5) 14–25, 14–30 13–29/Present 18–29, 14–30 1–4 (mostly 3) 1, 1 22–37 λ-shaped P. floridana (Ehlers, 1868) 2–3 5–8, 5–8 1–3 (mostly 1) 9–13, 9–12 9–15/Absent 15–23, 15–23 1 (rarely 0) 1, 1 (rarely 0 or with cones) 27–38 λ-shaped P. houbihuensis sp. nov. 2 5, 5 2 11, 12 19/Absent 16, 12 1 1, 1 33 χ-shaped P. longdongwanensis sp. nov. 3–4 8. 8 13 29, 29 24/Absent 33, 31 4–16 1 (1+2–6 cone), 1 (1+3–8 cone) 140–194 λ-shaped P. pangcahae sp. nov. 2–4 4–5, 4–5 2–5 12–15, 11–14 22–27/Present 22–30, 19–33 3 1, 1 (1+0–1 cone) 27–33 ɔc-shaped P. pseudocutrifera sp. nov. 2–3 5–8, 5–8 1–3 9–10, 8–11 8–14/Present 15–18, 12–21 0 1, 1 30–35 λ-shaped P. taitungensis sp. nov. 3–4 3–4, 3–5 2 6, 8–11 13–19/Present 19–25, 24–26 3 0–1, 1 28–30 ɔc-shaped Taxon\Categories DC/DL AC DC/DL MC DC/DL PC DL/ML PC NoPL GM in DL PC SP/SB AC SP/SB MC SP/SB PC AnC P. cultrifera (Grube, 1840) 0.6 0.6 0.4 2.2 Present/AC–MC 2 HoS, HeF/ HoS, HeF HoS, HeF/ HoS, HeF HoS, HeF/ HoS, HeF 2–4 P. floridana (Ehlers, 1868) 0.8 0.8 0.4 2.2 Absent 0 HoS, HeF/ HoS, HeF HoS, HeF/ HoS, HeF HoS, HeF/ HoS, HeF 4–5 P. houbihuensis sp. nov. 0.5 0.5 0.5 2.5 Present throughout 2 HoS, HeF/ HeF HoS, HeF/ HeF HoS, HeF / HeS, HeF 3 P. longdongwanensis sp. nov. 0.5 0.5 0.7 1.8 Present/AC 0 HoS, HeF/ HoS, HeF HoS, HeF/ HoS, HeF HoS, HeF/ HoS, HeF 4 P. pangcahae sp. nov. 0.8 0.6 0.3 1.8 Absent 1 HoS, HeF/ HeS, HeF HoS, HeF/ HeS, HeF HoS, HeF/ HeS, HeF 3–7 P. pseudocutrifera sp. nov. 0.8 0.8 0.4 2.3 Present throughout 0 HoS, HeF/ HeS, HeF HoS, HeF/ HeS, HeF HoS, HeF/ HeS, HeF 2–6 P. taitungensis sp. nov. 0.8 0.4 0.4 1.8 Present/MC 2 HoS, HeF/ HeF HoS, HeF/ HeS, HeF HoS, HeF/ HeS, HeF 3 Abbreviations: AC = anterior chaetigers; AnC = last chaetiger reached by anal cirri; DC = dorsal cirri; DL = dorsal ligule; GM = glandular mass; LT = lateral teeth; LTC = chaetigers reached by longest tentacular cirri; MC = mid-body chaetigers; NoPL = notopodial prechaetal lobe; PC = posterior chaetigers; RP = ridge pattern of areas VI–V–VI; SB = subacicular fascicle; SP = supra-acicular fascicle; TJ = teeth of jaws. page 8 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan respectively (Table 2, Hutchings et al. 1991: 253; Park and Kim 2017: 258, table 4). Collection and habitat information of present specimens indicate this species is widespread on rocky coasts in Taiwan. Perinereis cultrifera is originally described from the Mediterranean Sea and later reported from most temperate oceans (Grube 1840; Hutchings et al. 1991). However, taxonomic confusions from work of Fauvel (1932) leads to the suggestion by Hutchings et al. (1991) that additional distribution records of the species from other geographic regions, such as Marshall Islands, New Caledonia, India, South Africa and Madagascar, Japan, require verification. Park and Kim (2017: 256, fig. 6) suggested that all P. cultrifera reported from East China, Korea, Japan, and Taiwan are actually P. euiini. In the present study, the author follows the distribution range reported in Hutchings et al. (1991) and adds a verified additional location of the species from Taiwan. Perinereis daxiensis sp. nov. (Fig. 4, Table 3) urn:lsid:zoobank.org:act:E2B163CF-3B53-4156-A7CF2F6DBE69796B Material examined: Holotype, NMNS 8748-44, Daxi (24°56.59'N, 121°54.23'E), habitat type: IRHB, 25 April 2000. Etymology: The name is derived from the name of nearby village, Daxi, where the worm was collected. Description: Holotype, atoke, complete, body length 110.0 mm with 128 chaetigers, chaetiger 10 width 3.6 mm, excluding parapodia; beige in alcohol (Fig. 4A). Prostomium wider than long, lateral antennae antero-lateral, shorter than palps, palpophores globose, palpostyles spheroid. Four pairs of tentacular cirri, longest one reaching chaetiger 5. Two pairs of eyes, in trapezoidal arrangement. Tentacular belt about 1.4x longer than chaetiger 1. Pharynx with dark brown jaws, each with 5 teeth; paragnath pattern: I = 2, in Fig. 4. Perinereis daxiensis sp. nov.; holotype (NSNM 8748-44): A, anterior body region, dorsal view; B, close-up of areas V, VI and VIII of the pharynx; C, right parapodium, anterior view, chaetiger 10; D, right parapodium, anterior view, chaetiger 50; E, right parapodium, anterior view, chaetiger 90; F, neurochaetae of chaetiger 90. Abbreviations: HeF = heterogomph falciger. Scale bars: A = 1.0 mm; B = 0.1 mm; C–E = 0.2 mm; F = 0.02 mm. page 9 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan author herein treats P. neocaledonica as a valid species. In fact, Pruvot (1930: 54) commented that the type specimen of P. caeruleis is incomplete posteriorly and cannot be ascertain of its parapodial morphology on posterior chaetigers. On the contrary, P. neocaledonica is known to have greatly elongated dorsal ligule on posterior chaetigers (Pruvot 1930: 51–52, fig. IVb). With this evidence, P. neocaledonica should belong in group 3B. Despite morphological similarities between the two species, P. fugangensis sp. nov. can be distinguished from P. neocaledonica by having: 1) 10 small and many minute cones scattered on area V (versus one large and many minute cones); 2) short bars on area VI (versus cones); 3) smaller length ratio of expanded dorsal ligule to median ligule on posterior chaetigers (about 3.7 versus about 5.2 (based on the measurement from the drawing of fig. IVb in Pruvot 1930)); and 4) one elongated rectangle glandular mass in each of the center and proximal lobes of dorsal ligule on posterior chaetigers (versus one elongated rectangle glandular mass) (Figs. 6B, C, E, 7E; Pruvot 1930: 51–54, fig. IVb, pl. III, figs. 77–79). It is worth mentioning that there are some morphological discrepancies between P. neocaledonica reported by Wu (1967) and the type by Pruvot (1930) in several aspects. Wu (1967: 74, fig. 12d) showed that the length ratio of dorsal ligule to median ligule on posterior chaetiger is only about 3.2, whereas that of ratio in the type is about 5.2 (Pruvot 1930: 51, fig. IVb). Moreover, Wu (1967: 73) stated that P. neocaledonica has neuropodial heterogomph spinigers present only on posterior chaetigers, but Pruvot (1930: 52) acknowledged the presence of neuropodial heterogomph spinigers at the beginning of middle third of the body segments to posterior chaetigers. Perinereis houbihuensis sp. nov. (Fig. 8, Table 2) urn:lsid:zoobank.org:act:98CAF5A1-D840-4902-962830579ED51AAB Material examined: Holotype, NSNM 8748-54, Houbihu Harbor (21°56.32'N, 120°44.73'E), habitat type: SRHB, 19 November 2010. Etymology: The name is derived from the name of Houbihu Harbor, where the worm was collected. Description: Holotype, atoke, complete, body length 74.5 mm with 72 chaetigers, chaetiger 10 width 2.5 mm, excluding parapodia; beige in alcohol (Fig. 8A, B). Prostomium wider than long, lateral antennae antero-lateral, shorter than palps, palpophores globose, palpostyles spheroid. Four pairs of tentacular cirri, longest one reaching chaetiger 2. Two pairs of eyes, in trapezoidal arrangement. Tentacular belt longer than chaetiger 1. Pharynx with dark brown jaws, each with 5 teeth; paragnath pattern: I = 2 uneven size cones, in longitudinal line, larger cone with square base, located posteriorly; II = 11 (left), 12 (right), in 3 oblique rows; III = 19, in oval-shaped patch, without lateral teeth; IV = 16 (left), 12 (right), in 3 oblique rows, without bars; V = 1; VI = 1 (left), 1 (right), short bars; VII–VIII = 33, in 2 rows. Ridge pattern of areas VI–V–VI, χ-shaped (Fig. 8A, B, Table 2). Dorsal cirri digitiform with base bulged, attached 1/3 to base of dorsal ligule, about 0.5x as long as dorsal ligule on anterior chaetigers, medially attached to dorsal ligule, about 0.5x as long as dorsal ligule on mid-body to posterior chaetigers (Fig. 8C–E, Table 2). Dorsal ligule conical on anterior chaetigers, about 1.8x longer than median ligule, subconical on midbody to posterior chaetigers, about 2.3–2.5x longer than median ligule; center and proximal lobes of dorsal ligule each with one irregular-shaped glandular mass on posterior chaetigers (Fig. 8E, G, I, Table 2). Notopodial prechaetal lobe present throughout (Fig. 8C–F, I, Table 2). Median ligule with truncated tip on anterior chaetigers, as long as neuroacicular ligule, subconical on mid-body chaetigers, about 2.0x longer than neuroacicular ligule on mid-body chaetigers, about 2.0x long than neuroacicular ligule on posterior chaetigers (Fig. 8C–E). Neuroacicular ligule with subequal inferior and superior lobes throughout, about as long as ventral ligule on anterior to mid-body chaetigers, about 0.8x as long as ventral ligule on posterior chaetigers. Neuropodial postchaetal lobe absent. Ventral ligule conical on anterior chaetigers, subconical on midbody to posterior chaetigers. Ventral cirri mid-ventrally attached to ventral edge of parapodia, about as long as ventral ligule throughout (Fig. 8C–E). Notochaetae present from chaetiger 3 to posterior chaetigers, homogomph spinigers present throughout. Supra-acicular fascicle of neuropodia: homogomph spinigers and short-bladed heterogomph falcigers with serrations present throughout; some abnormal posterior chaetigers with only one simple chaeta and losing both heterogomph falcigers and heterogomph spinigers (Fig. 8I). Subacicular fascicle of neuropodia: shortbladed heterogomph falcigers with serrations present throughout, heterogomph spinigers present only on posterior chaetigers (Fig. 8F–H, J, K, Table 2); some abnormal posterior chaetigers losing both heterogomph falcigers and heterogomph spinigers (Fig. 8I). Pygidium with anus crenulated; anal cirri cirriform, as long as last 3 chaetigers (Table 2). Type locality: Houbihu Harbor, Pingtung County, Taiwan. page 16 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan Fig. 8. Perinereis houbihuensis sp. nov.; holotype (NSNM 8748-54): A, anterior body region, dorsal view; B, anterior body region, ventral view; C, right parapodium, anterior view, chaetiger 10; D, right parapodium, anterior view, chaetiger 35; E, right parapodium, anterior view, chaetiger 59; F, close-up of chaetiger 35, anterior view; G, close-up of chaetiger 56, anterior view; H, neuropodial chaetae of chaetiger 56; I, close-up of chaetiger 59, anterior view; J, K, neuropodial heterogomph falciger, chaetiger 10. Abbreviations: HeF = heterogomph falciger; HeS = heterogomph spiniger; HoS = homogomph spiniger; NoPL = notopodial prechaetal lobe; SC, simple chaeta. Scale bars: A, B = 0.5 mm; C–E = 0.2 mm; F, I = 0.1 mm; G = 0.2 mm, J, K = 0.02 mm. page 17 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan Distribution: Known only from type locality. Remarks: Perinereis houbihuensis sp. nov. has one bar-shaped paragnath on area VI of the pharynx and not greatly expanded notopodial dorsal ligule on posterior chaetigers, which would include it in group 1A proposed by Hutchings et al. (1991: 271) (Fig. 8A, E). Seven species in this group were reported from East and Southeast Asia, which are: Perinereis calmani (Monro, 1926), P. cultrifera (Grube, 1840), P. dongalae (Horst, 1924), P. euiini Park and Kim, 2017, P. floridana (Ehlers, 1868), P. helleri (Grube, 1878), and P. tenuisetis (Fauvel, 1915) (Wu 1967; Imajima 1972; Wu et al. 1981 1985; Sun and Yang 2004; Glasby et al. 2016; Park and Kim 2017). Of these seven species, only P. floridana has the similar paragnath patterns as P. houbihuensis sp. nov. on areas I, III, V and VI (2, 1, 19 without lateral teeth, and 1 versus 2, 1, 16 without lateral teeth and 1, respectively) (de León-González and Solís-Weiss 1998: 684). However, P. houbihuensis sp. nov. can be distinguished from P. floridana by having: 1) χ-shaped ridge pattern on areas V–VI–V (versus λ-shaped ridge pattern); 2) notopodial prechaetal lobe present on chaetigers of all body regions (versus absent); 3) the center and proximal lobes of dorsal ligule each with one irregular-shaped glandular mass on posterior chaetigers (versus absent); and 4) neuropodial heterogomph spinigers present only on posterior chaetigers (versus present on chaetigers of all body regions) (Fig. 8B, C, E, H, Table 2; de León-González and Solís-Weiss 1998: 684–685, fig. 6B–E). Hutchings et al. (1991: 255) suggested that the length ratio of dorsal cirri to dorsal ligule is not an reliable character for species identification in the 1A group of the genus and has not been used herein for comparing differences between congers. The differences between P. houbihuensis sp. nov. and four other new species of the 1A group described in the present study are discussed below. Perinereis hsinchuensis sp. nov. (Fig. 9, Table 3) urn:lsid:zoobank.org:act:E71CE585-7333-457B-91F1A5A306582487 Material examined: Holotype, NSNM 8748-55, Hsinchu Harbor (24°51.00'N, 120°55.48'E), habitat type: SRHB, 1 September 2019. Etymology: The name is derived from the Hsinchu Harbor, where the worm was collected. Description: Holotype, atoke, without posterior end, remaining body length 23.5 mm with 59 chaetigers, chaetiger 10 width 1.2 mm, excluding parapodia; beige in alcohol (Fig. 9A–C). Prostomium wider than long, lateral antennae antero-lateral, shorter than palps, palpophores globose, palpostyles spheroid. Four pairs of tentacular cirri, longest one reaching chaetiger 2. Two pairs of eyes, in trapezoidal arrangement. Tentacular belt about 1.4x longer than chaetiger 1. Pharynx with dark brown jaws, each with 6 teeth; paragnath pattern: I = 3 large cones, in longitudinal line; II = 16 (left), 17 (right), in 2–3 oblique rows; III = 21 (center region with 17 cones, in oval-shaped patch; 2 lateral regions, each with 1 or 3 cones); IV = 26 (left), 30 (right), in 4–5 oblique rows, without bars; V = 3, in triangle; VI = 3 (left), 3 (right), uneven-length smooth bars in transverse row; VII–VIII = 37, in 2 rows. Ridge pattern of areas VI–V–VI, χ-shaped (Fig. 9B and C, Table 3). Dorsal cirri digitiform, medially attached to base of dorsal ligule, about 0.7x as long as dorsal ligule on anterior chaetigers, attached 1/3 to base of dorsal ligule on mid-body chaetigers, about 0.8x as long as dorsal ligule, attached 2/3 to base of dorsal ligule on posterior chaetigers, about 0.5x as long as dorsal ligule (Fig. 9D– F, Table 3). Dorsal ligule subconical throughout, about 2.4x longer than median ligule on anterior chaetigers, about 1.9–2.0x longer than median ligule on mid-body to posterior chaetigers; center lobe of dorsal ligule with one round glandular mass on posterior chaetigers (Fig. 9D–F, Table 3). Notopodial prechaetal lobe absent (Table 3). Median ligule subconical throughout, about as long as neuroacicular ligule on anterior to mid-body chaetigers, about 1.8x longer than neuroacicular ligule on posterior chaetigers (Fig. 9D–F). Neuroacicular ligule with subequal inferior and superior lobes, as long as ventral ligule throughout. Neuropodial postchaetal lobe absent. Ventral ligule subconical throughout. Ventral cirri mid-ventrally attached to ventral edge of parapodia, as long as ventral ligule on anterior to mid-body chaetigers, about 1.2x longer than ventral ligule on posterior chaetigers (Fig. 9D–F). Notochaetae present from chaetiger 3 to posterior chaetigers, homogomph spinigers present throughout. Supra-acicular fascicle of neuropodia: homogomph spinigers and medium-sized blade heterogomph falcigers with serrations present throughout (Fig. 9G, H, Table 3). Subacicular fascicle of neuropodia: mediumsize blade heterogomph falcigers with serrations present throughout, heterogomph spinigers present only on anterior to mid-body chaetigers (Fig. 9G, H, Table 3). Type locality: Hsinchu Harbor, Hsinchu City, Taiwan. Distribution: Known only from type locality. Remarks: Perinereis hsinchuensis sp. nov. has an arc of three bar-shaped paragnaths on each side of area VI of the pharynx and not greatly expanded notopodial page 18 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan dorsal ligule on posterior chaetigers, which include it in group 3A, as well as the Perinereis nuntia species group (Fig. 9B, F; Hutchings et al. 1991: 271; Wilson and Glasby 1993: 259; Glasby and Hsieh 2006: 558; Villalobos-Guerrero 2019: 468). Of the 20 known species in this species group recognized by VillalobosGuerrero (2019), only P. viridis Glasby and Hsieh, 2006 is similar to P. hsinchuensis sp. nov., because both species have uneven bar-shaped paragnaths and number of paragnaths ranging in 2–4 on area VI, and presence of lateral paragnaths on area III (Fig. 9B, C, Table 3; Glasby and Hsieh 2006: 562, 569–570, fig. 9A–B, table 2; Villalobos-Guerrero 2019: 489). However, P. hsinchuensis sp. nov. differs from P. viridis in terms of having: 1) cones only on area IV (versus cones and bars), 2) three paragnaths on area V (versus one); 3) Fig. 9. Perinereis hsinchuensis sp. nov.; holotype (NSNM 8748-55): A, whole animal, lateral view; B, anterior body region, dorsal view; C, anterior body region, frontal view; D, right parapodium, anterior view, chaetiger 10; E, right parapodium, anterior view, chaetiger 24; F, right parapodium, anterior view, chaetiger 49; G, chaetae of chaetiger 24; H, chaetae of chaetiger 49. Abbreviations: HeF = heterogomph falciger; HeS = heterogomph spiniger; HoS = homogomph spiniger. Scale bars: A = 2.0 mm; B, C = 0.5 mm; D, E = 0.2 mm; F = 0.1 mm; G, H = 0.02 mm. page 19 of 57 Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan ɔc-shaped ridge pattern of area areas VI–V–VI (versus χ-shaped ridge pattern); 4) dorsal cirri about 0.5x as long as dorsal ligule on posterior chaetigers (versus as long as dorsal ligule); 5) one round glandular mass in the center lobe of dorsal ligule on posterior chaetigers (versus one irregular-shaped glandular mass in each of the center and proximal lobes of dorsal ligule); and 6) neuropodia without heterogomph spinigers on posterior chaetigers (versus present throughout all body regions) (Fig. 9B, C, F, H, Table 3; Glasby and Hsieh 2006: 562, 569–570, fig. 9A–D, table 2; Villalobos-Guerrero 2019: 489). The differences between P. hsinchuensis sp. nov. and eight other new species of the 3A group described in the present study are discussed below. Perinereis kaomeiensis sp. nov. (Fig. 10, Table 3) urn:lsid:zoobank.org:act:FBF66483-C273-4161-972B16B6C2233621 Material examined: Holotype, NMNS 3031-2, Kaomei (24°18.50'N, 120°32.42'E), habitat type: ISSB, coll. S-M Chao, 2 November 1997. Etymology: The name is derived from the name of nearby village, Kaomei, where the worm was collected. Description: Holotype, epitoke, complete, body length 98.0 mm with 180 chaetigers, chaetiger 10 width 5.0 mm, excluding parapodia; light brown in alcohol (Fig. 10A, B). Prostomium wider than long, lateral antennae antero-lateral, longer than palps, palpophores globose, palpostyles spheroid. Four pairs of tentacular cirri, longest one reaching chaetiger 8. Two pairs of eyes, in trapezoidal arrangement. Tentacular belt about 1.5x longer than chaetiger 1. Pharynx with dark brown jaws, each with 4 teeth; paragnath pattern: I = 9, in cluster; II = 17 (left), 18 (right), in 2 oblique rows; III = 54, in 5–6 transverse rows; IV = 22 (left), 25 (right), in 4–6 oblique rows, without bars; V = 5, in cluster; VI = 5 (left), 4 (right), even length short bars in transverse row; VII–VIII = 52, in 2–3 rows. Ridge pattern of areas VI– V–VI, ɔc-shaped (Fig. 10A–C, Table 3). Pre-natatory region: Dorsal cirri robust with filament distally on chaetiger 1 to 7, basally or medially attached to dorsal ligule, about 1.3x longer than dorsal ligule, digitiform on chaetiger 8 to 20, medially attached to dorsal ligule, about 0.8x as long as dorsal ligule. Dorsal ligule subconical. Notopodial prechaetal lobe present. Median ligule subconical. Neuroacicular ligule with predominant inferior lobe. Neuropodial postchaetal lobe absent. Ventral ligule subconical. Ventral cirri robust with filament distally on chaetiger 1 to 7, becoming digitiform from chaetiger 8 to 20, midventrally attached to ventral edge of parapodia, about 0.8x as long as ventral ligule. Notochaetae homogomph spinigers. Supra-acicular fascicle of neuropodia: homogomph spinigers and long blade heterogomph falcigers with narrow serrations. Subacicular fascicle of neuropodia: homogomph spinigers and long blade heterogomph falcigers with narrow serrations (Fig. 10D, J, Table 3). Natatory region: Dorsal cirri digitiform, medially attached to dorsal ligule, about 0.6x as long as dorsal ligule; dorsal cirrus with small lobe presence from chaetiger 21, becoming large auricular lobe from chaetiger 24 to mid-body chaetigers, reduced progressively in size thereafter, absent on posterior half of posterior chaetigers. Dorsal ligule subconical. Notopodial prechaetal lobe absent. Median ligule subconical throughout, slightly longer than neuroacicular ligule, with small lobe close to base of dorsal surface on all natatory chaetigers, with irregularshaped lobe at base of ventral surface on posteriorhalf of natatory chaetigers. Neuroacicular ligule with predominant inferior lobe, about as long as ventral ligule. Large neuropodial postchaetal lamella present on posterior-half of natatory chaetigers. Ventral ligule subconical, with small lobe close to base of dorsal surface throughout natatory chaetigers. Ventral cirri attached to base of parapodia, about 1.6x longer than ventral ligule with irregular-shaped dorsal and ventral lobes on anterior-half of natatory chaetigers, gradually reduced in size thereafter. Notochaetae homogomph spinigers absent, replaced by sesquigomph natatory chaetae. Supra-acicular fascicle of neuropodia: homogomph spinigers and heterogomph falcigers absent, replaced by sesquigomph natatory chaetae. Subacicular fascicle of neuropodia: homogomph spinigers and heterogomph falcigers absent, replaced by single sesquigomph natatory chaeta (Fig. 10E, F, H, I, K, Table 3). Post-natatory region: Dorsal cirri digitiform, medially attached to dorsal ligule, about 0.5x as long as dorsal ligule. Dorsal ligule subconical, not greatly expanded, about 2.1x longer than median ligule. Notopodial prechaetal lobe absent. Median ligule subconical, with small lobe close to base of dorsal surface on all chaetigers. Neuroacicular ligule with predominant inferior lobe, about as long as ventral ligule. Neuropodial postchaetal lobe absent. Ventral ligule subconical. Ventral cirri digitiform, with small irregularshaped lobe on dorsal surface, shorter than ventral ligule. Notochaetae homogomph spinigers absent. Supra-acicular fascicle of neuropodia: homogomph spinigers and heterogomph falcigers absent. Subacicular fascicle of neuropodia: single heterogomph falciger and single homogomph spiniger present (Fig. 10G, L, M, Table 3). Pygidium with anus crenulated, opened dorsally, page 20 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan Fig. 10. Perinereis kaomeiensis sp. nov.; holotype (NSNM 3031-2): A, whole animal, lateral view; B, anterior body region, dorsal view; C, paragnath patterns of the pharynx; D, left parapodium, anterior view, chaetiger 10; E, left parapodium, anterior view, chaetiger 24; F, left parapodium, anterior view, chaetiger 71; G, right parapodium, anterior view, chaetiger 145; H, close-up of notopodium, chaetiger 71; I, close-up of neuropodium, chaetiger 71; J, neuropodial heterogomph falciger, chaetiger 15; K, natatory chaeta, chaetiger 71; L, neuropodial heterogomph falciger, chaetiger 173; M, neuropodial heterogomph spiniger, chaetiger 15; N, posterior end of the body. Abbreviations: An = Anus; NC = natatory chaeta; NoPL = notopodial prechaetal lobe; SC, simple chaeta. Scale bars: A = 5.0 mm; B = 1.0 mm; C–G, N = 0.5 mm; H–M = 0.02 mm. page 21 of 57 Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan surrounded by papillae; anal cirri cirriform, as long as last 9 chaetigers (Fig. 10N). Type locality: Kaomei tidal flat, Taichung City, Taiwan. Distribution: Known only from type locality. Remarks: With an arc of 4–5 bar-shaped paragnaths on area VI of the pharynx and not greatly expanded notopodial dorsal ligule on posterior chaetigers, P. kaomeiensis sp. nov. can be categorized in group 3A, together with Perinereis nuntia species group (Fig. 10C, G, Table 3; Hutchings et al. 1991: 271; Wilson and Glasby 1993: 259; Glasby and Hsieh 2006: 558; Villalobos-Guerrero 2019: 468). Of the 20 species in this species group recognized by VillalobosGuerrero (2019), only P. mictodonta (Marenzeller, 1879) and P. nuntia (Lamarck, 1818) have paragnath patterns on areas V and VI that are somewhat similar to P. kaomeiensis sp. nov., which have 0–5 cones on area V and 4–10 bars on area VI (Fig. 10C, Table 3; Glasby and Hsieh 2006: 562, table 2; Villalobos-Guerrero 2019: 489). However, P. kaomeiensis sp. nov. differs from P. mictodonta by having; 1) greater number of paragnaths on area I (9 versus 1–5 (type) or 2–6 (Taiwan); 2) no lateral paragnaths on area III (versus present); 3) evenlength bars on area VI (versus uneven-length bars); 4) ɔc-shaped ridge pattern of areas VI–V–VI (versus χ-shaped ridge pattern); 5) notopodial prechaetal lobe present on pre-natatory chaetigers (versus absent in all chaetigers); 6) smaller length ratio of dorsal cirri to dorsal ligule on anterior and posterior chaetigers (about 0.8 and about 0.5 versus 1.07 and 1.04, respectively); 7) no glandular mass in the proximal lobe of dorsal ligule (versus two irregular-shaped glandular masses); 8) only one small lobe at dorsal base of ventral cirri on anteriorhalf of post-natatory chaetigers (versus auricular lobes continuing to within 10–25 chaetigers before pygidium); and 9) long blade neuropodial heterogomph falcigers (medium-sized blade heterogomph falcigers) (Fig. 10C, D, G, L, Table 3; Glasby and Hsieh 2006: 559–562, fig. 5A–F, table 2; Villalobos-Guerrero 2019: 489). Perinereis kaomeiensis sp. nov. can be distinguished from P. nuntia by having; 1) greater number of paragnaths on areas I and III (9 and 54 versus 1–3 (Red Sea) or 0–5 (all) and 9–17 (Red Sea) or 1–30 (all), respectively); 2) no lateral paragnaths on area III (versus present); 3) only bars on area VI (versus bars and cones); 4) ɔc-shaped ridge pattern of areas VI–V–VI (versus χ-shaped ridge pattern); 5) notopodial prechaetal lobe present on pre-natatory chaetigers (versus absent in all chaetigers) and 6) long blade neuropodial heterogomph falcigers (medium-sized blade heterogomph falcigers) (Fig. 10C, D, L, Table 3; Glasby and Hsieh 2006: 562–565, fig. 6A–E, table 2; Villalobos-Guerrero 2019: 471, 489). The differences between P. kaomeiensis sp. nov. and eight other new species of group 3A described in the present study are discussed below. Perinereis kebalanae sp. nov. (Fig. 11, Table 4) urn:lsid:zoobank.org:act:E8412AC0-FAFC-4879-AAF7A05F4C296129 Material examined: Holotype, NSNM 8748-56, Daxi (24°56.59'N, 121°54.23'E), habitat type: IRHB, 25 April 2000. Paratypes: 1 specimen, NSNM 874857, Shimen (25°17.85'N, 121°34.14'E), habitat type: IRHB, 17 March 2006; 1 specimen, NSNM 8748-58, Jihuei (23°06.87'N, 121°24.21'E), habitat type: IRHB, 27 March 2014. Etymology: The name is derived from the Kebalan aboriginal tribe, who has settled to northeastern of Taiwan in 13th century. Description: Based on holotype (atoke, complete) and paratypes (atoke, complete): body length 39.0 (32.5– 52.5) mm with 101 (103–105) chaetigers, chaetiger 10 width 2.0 (2.6–3.0) mm, excluding parapodia; beige in alcohol (Fig. 11A). Prostomium wider than long, lateral antennae antero-lateral, as long as palps, palpophores globose, palpostyles spheroid. Four pairs of tentacular cirri, longest one reaching chaetiger 3. Two pairs of eyes, in trapezoidal arrangement. Tentacular belt about 1.4x (1.2–1.3x) longer than chaetiger 1. Pharynx with dark brown jaws, each with 6 teeth; paragnath pattern: I = 1; II = 19 (19–25) (left), 25 (16–20) (right), in 4 oblique rows; III = 35 (30–35), in 4 transverse rows; IV = 50+4 p-bars near jaw (49–54+3–4 p-bars) (left), 52+4 p-bars near jaw (50+4 p-bars) (right), in 4–6 oblique rows; V = 1; VI = 1 (left), 1 (right), smooth bars; VII– VIII=37 (33–38), in 3 rows. Ridge pattern of areas VI– V–VI, u-shaped (Fig. 11B, Table 4). Dorsal cirri digitiform throughout, medially attached to dorsal ligule, about 1.2–1.3x longer than dorsal ligule on anterior to mid-body chaetigers, subdistally attached to dorsal ligule on posterior chaetigers, about 0.6x as long as dorsal ligule (Fig. 11C–E). Dorsal ligule conical on anterior chaetigers, about 2.0x longer than median ligule, subconical on midbody chaetigers, about 2.3x longer than median ligule, becoming rectangular and greatly elongated on posterior chaetigers, about 3.5x longer than median ligule (Fig. 11C–E). Notopodial prechaetal lobe absent. Median ligule conical, about 1.7x longer than neuroacicular ligule on anterior chaetigers, subconical on mid-body to posterior chaetigers, about 1.5x longer than neuroacicular ligule on mid-body chaetigers, about as long as neuroacicular ligule on posterior chaetigers page 22 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan Table 4. Key characters of Perinereis species described in the present study of group 1B Taxon\Categories LTC TJ I IIL, IIR III/LT IVL, IVR V VIL, VIR VII–VIII RP VI–V–VI P. kebalanae sp. nov. 3 6, 6 1 19–25, 20–25 30–35/Absent 50–54+4 bars, 5?–52+2-4 bars 1 1, 1 33–37 u-shaped P. nigropunctata (Horst, 1889) 1–7 5–6, 5–7 3–11 6–23, 6–25 20–29/Present 17–31, 19–35 2–5 1, 1 25–39 λ-shaped P. wanlitongensis sp. nov. 3–4 5–6. 5–6 2 11–12, 13 20/Present 22–24, 24–27 3–4 1, 1 23–33 λ-shaped Taxon\Categories DC/DL AC DC/DL MC DC/DL PC DL/ML PC NoPL GM in DL PC SP/SB AC SP/SB MC SP/SB PC AnC P. kebalanae sp. nov. 1.3 1.2 0.6 3.5 Absent 0 HoS, HeF/ HeF HoS, HeF/ HeS, HeF HoS, HeF/ HeS, HeF 3–7 P. nigropunctata (Horst, 1889) 1.0 0.5 0.4 3.3 Present throughout 1HoS, HeF/ HeS, HeF HoS, HeF/ HeS, HeF HoS, HeF/ HeS, HeF 2–4 P. wanlitongensis sp. nov. 0.8 0.8 0.3 4.2 Absent 3 HoS, HeF/ HeS, HeF HoS, HeF/ HeS, HeF HoS, HeF/ HeS, HeF 3–8 Abbreviations: AC = anterior chaetigers; AnC = last chaetiger reached by anal cirri; DC = dorsal cirri; DL = dorsal ligule; GM = glandular mass; LT = lateral teeth; LTC = chaetigers reached by longest tentacular cirri; MC = mid-body chaetigers; NoPL = notopodial prechaetal lobe; PC = posterior chaetigers; RP = ridge pattern of areas VI–V–VI; SB = subacicular fascicle; SP = supra-acicular fascicle; TJ = lateral teeth of jaws. Fig. 11. Perinereis kebalanae sp. nov.; holotype (NSNM 8748-56): A, anterior body region, dorsal view; B, paragnath patterns of the pharynx; C, right parapodium, anterior view, chaetiger 10; D, right parapodium, anterior view, chaetiger 36; E, right parapodium, anterior view, chaetiger 78; F, G, neuropodial heterogomph falciger, chaetiger 76; H, neuropodial heterogomph spiniger, chaetiger 76. Scale bars: A = 1.0 mm; B = 0.5 mm; C–E = 0.2 mm; F–H = 0.02 mm. page 23 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan (Fig. 11C–E). Neuroacicular ligule with subequal inferior and superior lobes throughout, slightly longer than ventral ligule throughout. Neuropodial postchaetal lobe absent. Ventral ligule subconical throughout. Ventral cirri midventrally attached to ventral edge of parapodia, about as long as ventral ligule throughout (Fig. 11C–E). Notochaetae present from chaetiger 3 to posterior chaetigers, homogomph spinigers present throughout. Supra-acicular fascicle of neuropodia: homogomph spinigers and short-bladed heterogomph falcigers with serrations present throughout. Subacicular fascicle of neuropodia: short-bladed heterogomph falcigers with serrations present throughout, heterogomph spinigers present on mid-body to posterior chaetigers (Fig. 11F–H, Table 4). Pygidium with anus crenulated; anal cirri cirriform, as long as last 7 (1–3) (n = 3) chaetigers. Type locality: Daxi, Yilan County, Taiwan. Distribution: Know from type locality, Shimen (New Taipei City) and Jihuei (Taitung County), Taiwan. Remarks: Perinereis kebalanae sp. nov. has one bar-shaped paragnath on area VI of the pharynx and greatly expanded notopodial dorsal ligule on posterior chaetigers, which implies it be categorized in group 1B proposed by Hutchings et al. (1991: 271) (Fig. 11B, E, Table 4). Six species in this group were reported from East and Southeast Asia, which are: Perinereis amblyodonta (Schmarda, 1861), P. barbara (Monro, 1926), P. malayana (Horst, 1889), P. nigropunctata (Horst, 1889), P. obfuscata (Grube, 1878), and P. suluana (Horst, 1924) (Wu 1967; Wu et al. 1981 1985; Sun and Yang 2004; Glasby et al. 2016). Of these six species, only P. amblyodonta and P. barbara are similar to P. kebalanae sp. nov., because all have conical and bar-shaped paragnaths on area IV (Fig. 11B, Horst 1889: 168; Fauvel 1915: 7; Hutchings et al. 1991: 248; 250, 257–258, 263). However, P. kebalanae sp. nov. can be distinguished from P. amblyodonta by having: 1) one conical paragnath on area I (versus 2–5); 2) only bar-shaped paragnaths on area VI (versus bar-shaped and conical paragnaths); 3) dorsal cirri not greatly exceeding dorsal ligule in length, with about 1.2–1.3x longer than dorsal ligule on anterior chaetigers (versus greatly exceeding dorsal ligule in length); 4) greater length ratio of dorsal cirri to dorsal ligule on posterior chaetigers (about 0.6 versus about 0.3 (based on measurement from the drawing of fig. 3f in Hutchings et al. 1991)); 5) smaller length ratio of dorsal ligule to median ligule on posterior chaetigers (about 3.5 versus about 5.0 (based on measurement from the drawing in fig. 3f in Hutchings et al. 1991)); 6) no notopodial prechaetal lobe (versus present on anterior chaetigers); and 7) neuropodial heterogomph spinigers present on mid-body to posterior chaetigers (versus absent on chaetigers of all body regions) (Fig. 11B, C, E, H, Table 4; Hutchings et al. 1991: 247–248, fig. 3a–f). Perinereis kebalanae sp. nov. is clearly different from P. barbara by having: 1) greater number of paragnaths on areas II and III (15–29 and 30–35 versus 6–14 and 3–7, respectively); 2) greater number of cones on area IV (50–54 versus 9–23); 3) fewer number of paragnaths on area V (1 versus 2–7); 4) only barshaped paragnaths on area VI (versus bar-shaped and conical paragnaths); 5) fewer number of paragnaths on areas VII–VIII (33–37 versus 45–101); 6) dorsal cirri subdistally attached to dorsal ligule on posterior chaetigers (versus attached 2/3 from the base of dorsal ligule); 7) greater dorsal cirri to dorsal ligule length ratio on anterior, mid-body, and posterior chaetigers (1.3, 1.2 and 0.6 versus 0.6, 0.5, and 0.5, respectively (based on the measurement from fig. 4b, d, e in Hutchings et al. 1991)); 8) dorsal ligule rectangular basally, about 3.5x longer than median ligule on posterior chaetigers (versus very broad basally and curved dorsally, about 2.5x (based on the measurement from fig. 4e in Hutchings et al. 1991) longer than median ligule on posterior chaetigers); 9) no notopodial prechaetal lobe (versus present on anterior to mid-body chaetigers); and 10) neuropodial heterogomph spinigers present on midbody to posterior chaetigers (versus absent on chaetigers of all body regions) (Fig. 11B–E, H, Table 4; Hutchings et al. 1991: 249–250, fig. 4b, d, e). The differences between P. kebalanae sp. nov. and the other new species of group 1B described in the present study are discussed below. Perinereis liuqiuensis sp. nov. (Fig. 12, Table 3) urn:lsid:zoobank.org:act:B7E103C2-8F32-42DD-BF8FE2C98DD915FF Material examined: Holotype, NSNM 8748-59, Yufu (22°20.90'N, 120°23.38'E), habitat type: ISSB, 11 May 2000. Etymology: The name is derived from the name of a small offshore island, Liuqiu, southwestern Taiwan, where the worm was collected. Description: Holotype, atoke, complete, body length 122.0 mm with 167 chaetigers, chaetiger 10 width 4.2 mm, excluding parapodia; beige in alcohol (Fig. 12A). Prostomium wider than long, lateral antennae antero-lateral, shorter than palps, palpophores globose, palpostyles spheroid. Four pairs of tentacular cirri, longest one reaching chaetiger 5. Two pairs of eyes, in trapezoidal arrangement. Tentacular belt about 1.3x longer than chaetiger 5. Pharynx with dark brown jaws, each with 3 teeth; paragnath pattern: I = 3, in page 24 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan longitudinal line; II = 9 (left), 12 (right), in cluster; III = 17 (center region with 13 cones, in 3 transverse rows; 2 lateral regions, each with 2 cones in longitudinal line); IV = 17 (left), 22 (right), in 3 oblique rows, without bars; V = 3, in triangle; VI = 9 (left), 9 (right), even length short bars in transverse row; VII–VIII = 29, in 2 rows. Ridge pattern of areas VI–V–VI, ɔc-shaped (Fig. 12B, Table 3). Dorsal cirri digitiform, medially attached to dorsal ligule throughout, about 0.5x as long as dorsal ligule on anterior to mid-body chaetigers, about 0.3x as long as dorsal ligule on posterior chaetigers (Fig. 12C–E, Fig. 12. Perinereis liuqiuensis sp. nov.; holotype (NSNM 8748-59): A, anterior body region, dorsal view; B, close-up of areas V, VI and VIII of the pharynx; C, right parapodium, anterior view, chaetiger 10; D, right parapodium, anterior view, chaetiger 57; E, right parapodium, anterior view, chaetiger 115; F–G, neuropodial heterogomph falciger, chaetiger 59; H, chaetae of chaetiger 57. Abbreviations: HeF = heterogomph falciger; HeS = heterogomph spiniger; HoS = homogomph spiniger. Scale bars: A = 1.0 mm; B–E = 0.2 mm; F–H = 0.01 mm. page 25 of 57 Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan Pharynx with dark brown jaws, each with 3–6 (n = 22) teeth; paragnath pattern: I = 1–6 (mostly 2–5, in cluster or longitudinal line, one case of 1 and two cases of 6, n = 22, same sample size on following areas); II = 14–26 (left), 12–25 (right), in 2–4 oblique rows; III = 15–32 (center region with 11–24 cones, in 3–4 transverse rows; mostly 2 lateral regions, each with 1–6 cones, three case of 3 lateral regions, outer region with 1–2 cones); IV = 23–42 (left), 23–42 (right), in 3–7 oblique rows, without bars; V = 1–4 (mostly 3, in triangle or transverse row, one case of 1 cone, two cases of 2 cones, four cases of 4 cones); VI = 3–9 uneven-length bars, innermost and outermost longest (left), 3–8 uneven-length bars, innermost and outermost longest (right); VII–VIII = 20– 39, in 2 rows, posterior row zigzagged. Ridge pattern of areas VI–V–VI, χ-shaped (Fig. 15A, B, Table 3). Dorsal cirri digitiform, medially attached dorsal ligule throughout, about 0.8x as long as dorsal ligule on anterior to mid-body chaetigers, about 0.5x as long as dorsal ligule on posterior chaetigers (Fig. 15C–E, Table 3). Dorsal ligule subconical throughout, about 2.0x longer than median ligule on anterior to mid-body chaetigers, about 1.3x longer than median ligule on posterior chaetigers; center lobe of dorsal ligule with one irregular-shaped glandular mass on posterior chaetigers (Fig. 15C–E). Notopodial prechaetal lobe absent (Table 3). Median ligule subconical throughout, greatly longer than neuroacicular ligule throughout (Fig. 15C– E). Neuroacicular ligule with prominent inferior lobe on anterior to mid-body chaetigers, about as long as ventral ligule, inferior and superior lobes subequal in length on posterior chaetigers, about as long as ventral ligule. Neuropodial postchaetal lobe absent. Ventral cirri digitiform, mid-ventrally attached to ventral edge of parapodia on anterior to mid-body chaetigers, about 0.9x as long as ventral ligule, distally attached to ventral ligule on posterior chaetigers, about 0.6x as long as ventral ligule (Fig. 15C–E). Notochaetae present from chaetiger 3 to posterior chaetigers, homogomph spinigers present throughout. Supra-acicular fascicle of neuropodia: homogomph spinigers and medium-sized blade heterogomph falcigers with serrations present throughout. Subacicular fascicle of neuropodia: medium-sized blade heterogomph falcigers with serrations and heterogomph spinigers present throughout (Fig. 15F, Table 3). Pygidium with anus crenulated; anal cirri cirriform, as long as last 4–8 (n = 5) chaetigers. Remarks: The morphology of examined specimens in the present study agrees with description of P. mictodonta (Marenzeller, 1879) in Glasby and Hsieh (2006: 599–561, fig. 5A–F) (Fig. 15A–F, Table 3). All examined specimens of P. mictodonta in the present study were mostly collected from soft bottom on river mouths and coastal flats of central-west Taiwan, which largely agree with distribution of this species in Taiwan reported by Glasby and Hsieh (2006: 555, fig. 1). Glasby and Hsieh (2006: 555, fig. 1) commented that no polychaete in the Perinereis nuntia group were found from river mouths on east coasts of Taiwan. However, the present distribution record of P. mictodonta in Taiwan showed one exception. One specimen of P. mictodonta was collected from rocky tide pool in coasts of Wushibi, eastern Taiwan. Presumably, windy seasons on east coasts of Taiwan provide suitable temporal living environment in rocky tide pool (i.e., sediment and algae brought in by strong wave actions) for larvae of P. mictodonta to settle and grow in that environment. This favorable living environment of biota vanished during summer with weak wave actions and high evaporation. Perinereis nigropunctata (Horst, 1889) (Fig. 16, Table 4) Nereis nigro-punctata Horst 1889: 171, pl. 8, figs. 1–3. Perinereis nigro-punctata Gravier 1901: 188–191, text-figs. 190–193, table 2, pl. 11, fig. 49. Perinereis marjorii Southern 1921: 595–597, text-figs. 7 8a–c, pl. 23, fig. 10A–G. Nereis (Perinereis) yorkensis Augener 1922: 24, fig. 6a–e. Nereis (Perinereis) nigropunctata Horst 1924: 171. Perinereis nigropunctata Monro 1931a: 16; Fauvel 1953: 210, fig. 107b–f; Day 1967: 337, fig. 14.13r–v; Wu 1967: 64–66, fig. 9a–d; Hartmann-Schröder 1979: 116–117, figs. 203–206; Hutchings et al. 1991: 256–257, fig. 10a–e. Examined material: 1 specimen, NMNS 874893, Linshanbi (25°16.99'N, 121°30.59'E), habitat type: IRHB, 1 November 2003; 3 specimens, NMNS 874894–96, Wanlitong (21°59.73'N, 120°42.26'E), habitat type: IRHB, 16 December 2007; 2 specimens, NMNS 8748-97–98, Jihuei (23°06.87'N, 121°24.21'E), habitat type: IRHB, 27–28 March, 2014; 3 specimens, NMNS 8748-99–101, Jihuei (23°06.87'N, 121°24.21'E), habitat type: IRHB, 27 September, 2014; 9 specimens, NMNS 8748-102–110, Jihuei (23°06.87'N, 121°24.21'E), habitat type: IRHB, 28–29 April, 2017; 4 specimens, NMNS 8748-111–114, Shadao (21°54.78'N, 120°50.83'E), habitat type: IRHB, 17 October 2020. Description: Based on 11 complete specimens (NMNS 8748-93, NMNS 8748-95–96, NMNS 8748104, NMNS 8748-106–107, NMNS 8748-109, NMNS 8748-111–114; all atoke) and 11 incomplete specimens (NMNS 8748-94, NMNS 8748-97–103, NMNS 8748105, NMNS 8748-108, NMNS 8748-110; all atoke): Body length 61.0 (10.5–57.0, n = 11) mm with 75 (60– 79, n = 11) chaetigers, chaetiger 10 width 2.5 (1.0–2.1, page 32 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan n = 11) mm, excluding parapodia; beige to dark brown in alcohol (Fig. 16A–D). Prostomium wider than long, lateral antennae antero-lateral, shorter than palps, palpophores globose, palpostyles spheroid. Four pairs of tentacular cirri, longest one reaching chaetiger 2 (1–7, n = 20). Two pairs of eyes, in trapezoidal arrangement. Tentacular belt about 1.3x (1.2–1.4x, n = 20) longer than chaetiger 1. Pharynx with dark brown jaws, each with 6 teeth; paragnath pattern: I = 5 (3–11, n = 20, same sample size on following areas), in triangle; II = 15 (6–23) (left), 16 (6–22) (right), in 2–3 oblique rows; III = 23 (12–30) (center region with 19 (8–25) cones, in 4 (3–4) transverse rows; 2 lateral regions, each with 2 (1–3) cones, in longitudinal line); IV = 20 (8–32) (left), 19 (9–35) (right), in 4 (4–6) oblique rows, without bars; V = 3 (1–5), in triangle (cluster, T-shaped or V-shaped); VI = 1 (1) (left), 1 (mostly 1, one case of 1+ 0–1 cone) (right), shield-shaped bars; VII–VIII = 37 (18–39), in 2–3 rows. Ridge pattern of areas VI–V–VI, λ-shaped (Fig. 16A–D, Table 4). Dorsal cirri digitiform throughout, medially attached to dorsal ligule on anterior to mid-body chaetigers, about as long as dorsal ligule on anterior chaetigers, about 0.5x as long as dorsal ligule, attached 2/3 to base of dorsal ligule on posterior chaetigers, about 0.4x longer than dorsal ligule (Fig. 16E–G, Table 4). Dorsal ligule subconical with blunt tip on anterior chaetigers, as long as median ligule, subconical on mid-body to posterior chaetigers, about 2.0x longer than median ligule, base of dorsal ligule bulged and elongated, about 3.3x longer than median ligule on posterior chaetigers; center lobe of dorsal ligule with one irregular-shaped glandular mass (Fig. 16E–G). Notopodial prechaetal lobe present throughout (Fig. 16E–G, Table 4). Median ligule conical on anterior chaetigers, about 1.4x longer than neuroacicular ligule, subconical on mid-body to posterior chaetigers, about 1.3–1.4x longer than neuroacicular ligule (Fig. 16E–G). Neuroacicular ligule with predominant inferior lobe on anterior chaetigers, inferior and superior lobes subequal in length on posterior half of mid-body to posterior chaetigers, about as long as ventral ligule. Neuropodial postchaetal lobe absent. Ventral ligule subconical throughout. Ventral cirri basally attached to ventral ligule, about 0.6x as long as ventral ligule on anterior chaetigers, about as long as ventral ligule on posterior chaetigers (Fig. 16E–G). Notochaetae present from chaetiger 3 to posterior chaetigers, homogomph spinigers present throughout. Supra-acicular fascicle of neuropodia: homogomph spinigers and short-bladed heterogomph falcigers with serrations present throughout. Subacicular fascicle of neuropodia: short-bladed heterogomph falcigers with serrations and heterogomph spinigers present throughout (Fig. 16H, I, Table 4). Pygidium with anus crenulated; anal cirri Fig. 16. Perinereis nigropunctata (Horst, 1889); A, B, E–I (NSNM 8748-113); C, D (NSNM 8748-110): A, anterior body region, dorsal view; B, anterior body region, frontal view;; C, anterior body region, dorsal view; D, anterior body region, ventral view; E, right parapodium, anterior view, chaetiger 10; F, right parapodium, anterior view, chaetiger 30; G, right parapodium, anterior view, chaetiger 55; H, neuropodial subacicular fascicle chaetae, chaetiger 10; I, neuropodial subacicular fascicle chaetae, chaetiger 54. Abbreviations: HeF = heterogomph falciger; HeS = heterogomph spiniger; NoPL = notopodial prechaetal lobe. Scale bars: A–D = 0.5 mm; E–G = 0.2 mm; H, I = 0.02 mm. page 33 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan cirriform, as long as last 4 (2–6) (n = 9) chaetigers (Table 4). Distribution: North and West Australia, Red Sea, Indian Ocean (India, Madagascar, Marshall Islands), Southeast Asia (Borneo, Malaysia, Singapore), Taiwan (Hutchings et al. 1991). Remarks: Morphology of present specimens agree with descriptions in Horst (1889), Wu (1967) and Hutchings et al. (1991). Moreover, collection locations of the present material also agree with the distribution of the species reported in Wu (1967) (see Fig. 1). Paragnath pattern on area III of the pharynx in P. nigropunctata (Horst, 1889) shows discrepancy between different reports. Horst (1889, collection locations: Malaysia), Wu (1967, collection locations: Taiwan) and Hutchings et al. (1991, collection locations: North and West Australia) noted that this species has lateral groups of cones on area III of the pharynx, whereas other reports (i.e., Gravier (1901), collection locations: Red Sea, Southern (1921), collection locations: India; Augener (1922), collection locations: North Australia, Fauvel (1953), collection locations: India; Day (1967), collection locations: Red Sea; Hartmann-Schroder (1979), collection locations: Malaysia; Hylleberg et al. (1986), collection locations: Malaysia) stated otherwise. The reason for this discrepancy between different geographic locations of the species is unclear. Perinereis pangcahae sp. nov. (Fig. 17, Table 2) urn:lsid:zoobank.org:act:B134E1BE-5E30-4AC0-ACDBF5BCC4F680C7 Material examined: Holotype, NSNM 8748-115, Jihuei (23°06.87'N, 121°24.21'E), habitat type: IRHB, 28 April 2017. Paratypes: 3 specimens, NSNM 8748116–118, Jihuei (23°06.87'N, 121°24.21'E), habitat type: IRHB, 29 April 2017; 1 specimen, NSNM 8748-119, Jihuei (23°06.87'N, 121°24.21'E), habitat type: IRHB, 27 March 2014. Non-types: 4 specimens, NSNM 8748120–123, Jihuei (23°06.87'N, 121°24.21'E), habitat type: IRHB, 27–28 March 2014; 3 specimens, NSNM 8748-124–126, Jihuei (23°06.87'N, 121°24.21'E), habitat type: IRHB, 28–29 April 2017. Etymology: The name is derived from the Pangcah aboriginal tribe of eastern Taiwan, as a tribute to their glittering cultures. Description: Based on holotype (NSNM 8748115, complete specimen; atoke), paratypes (NSNM 8748-116–119, 4 complete specimens; all atoke) and non-types (7 incomplete specimens; all atoke): holotype, atoke, body length 98.5 (73.5–111.5, n = 4) mm with 155 (136–160, n = 4) chaetigers, chaetiger 10 width 2.6 (2.7–4.5, n = 4) mm, excluding parapodia; light to dark brown in alcohol (Fig. 17A–C). Prostomium wider than long, lateral antennae antero-lateral, as long as (or Fig. 17. Perinereis pangcahae sp. nov.; A, E–H, holotype (NSNM 8748-115); B, C, paratype (NSNM 8748-124); C, paratype (NSNM 8748-116): A–C, anterior body region, dorsal view; D, close-up of areas V, VI and VIII of the pharynx; E, right parapodium, anterior view, chaetiger 10; F, right parapodium, anterior view, chaetiger 55; G, right parapodium, anterior view, chaetiger 105; H, chaetae of chaetiger 10. Abbreviations: HeF = heterogomph falciger; HeS = heterogomph spiniger. Scale bars: A–C = 1.0 mm; D–G = 0.5 mm; H = 0.02. page 34 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan shorter) than palps, palpophores globose, palpostyles spheroid. Four pairs of tentacular cirri, longest one reaching chaetiger 3 (2–5, n = 10). Two pairs of eyes, in trapezoidal arrangement. Tentacular belt about 1.2x (1.1–1.4x) longer than chaetiger 1. Pharynx with dark brown jaws, each with 4 (4–5, n = 11) teeth; paragnath pattern: I = 4 (2–5, n = 10), in cluster (same sample size on remaining areas ); II = 13 (9–15) (left), 11 (8–14) (right), in 3 oblique rows; III = 25 (17–32) (center region with 20 (13–25) cones, in 4 (3–5) transverse rows; 2 lateral regions, each with 2 (2–5) or 3 (2–4) cones in longitudinal line); IV = 30 (20–41) (left), 31 (19–36) (right), in 4 (4–6) oblique rows, without bars; V = 3, in triangle; VI = 1 (1) (left), 1+1 cone (1) (right), chevron-shaped bars; VII–VIII = 29 (21–33), in 2–3 (2–4) rows. Ridge pattern of areas VI–V–VI, ɔc-shaped (Fig. 17D, Table 2). Dorsal cirri digitiform throughout, attached 1/3 to base of dorsal ligule on anterior to mid-body chaetigers, about 0.8x as long as dorsal ligule on anterior chaetigers, about 0.6x as long as dorsal ligule on midbody chaetigers, medially attached to dorsal ligule on posterior chaetigers, about 0.3x as long as dorsal ligule (Fig. 17E–G, Table 2). Dorsal ligule subconical, about 2.7x longer than median ligule on anterior chaetigers, about 1.9x longer than median ligule on mid-body to posterior chaetigers; proximal lobe with one irregular-shaped glandular mass on mid-body chaetigers, center and proximal lobes with one large irregular-shaped glandular mass on posterior chaetigers (Fig. 17E–G). Notopodial prechaetal lobe absent (Table 2). Median ligule subconical throughout, about 1.4x longer than neuroacicular ligule on anterior chaetigers, about 1.7–1.8x longer than neuroacicular ligule on midbody to posterior chaetigers (Fig. 17E–G). Neuroacicular ligule with predominant inferior lobe, about 0.5x as long as ventral ligule on anterior chaetigers, inferior and superior lobes subequal in length on mid-body to posterior chaetigers, about 0.7x as long as ventral ligule. Neuropodial postchaetal lobe absent. Ventral ligule subconical throughout. Ventral cirri mid-ventrally attached to ventral edge of parapodia, about 0.6x as long as ventral ligule on anterior chaetigers, about 0.7x as long as ventral ligule on mid-body chaetigers, about 0.6x as long as ventral ligule on posterior chaetigers (Fig. 17E–G). Notochaetae present from chaetiger 3 to posterior chaetigers, homogomph spinigers present throughout. Supra-acicular fascicle of neuropodia: homogomph spinigers and medium-sized blade heterogomph falcigers with serrations present throughout. Subacicular fascicle of neuropodia: medium-sized blade heterogomph falcigers with serrations and heterogomph spinigers present throughout (Fig. 17H, Table 2). Pygidium with anus crenulated; anal cirri cirriform, as long as last 7 chaetigers. Type locality: Jihuei, Taitung County, Taiwan. Distribution: Known only from the type locality. Remarks: Perinereis pangcahae sp. nov. is included in group 1A by having one bar-shaped paragnath on area VI of the pharynx and not greatly expanded notopodial dorsal ligule on posterior chaetigers (Hutchings et al. 1991: 271) (Fig. 17D, G, Table 2). Of the seven species in this group reported from East and South Asia (see the Remarks section in P. houbihuensis sp. nov. for the name of these seven species), P. pangcahae sp. nov. is similar to P. cultrifera (Grube, 1840) and P. helleri (Grube, 1878), which all have lateral teeth on area III and 3 cones on area V (Fauvel 1915: 7; Horst 1924: 174; Hutchings et al. 1991: 250, 253, 255; de Leon-Gonzalez and SolisWeiss 1998: 684; Park and Kim 2017: 256, 258, tables 2, 4). However, P. pangcahae sp. nov. differs from P. cultrifera by having: 1) greater number of paragnaths on area III (22–27 versus 5–11 or 10–12); 2) chevronshaped bar on area VI (versus short straight bar); 2) ɔcshaped ridge pattern of areas VI–V–VI (versus λ-shaped ridge pattern); 3) one large irregular-shaped glandular mass on posterior chaetigers (versus ); 4) no notopodial prechaetal lobe on chaetigers of all body regions (versus present on anterior chaetigers); 5) neuroacicular ligule with predominant inferior lobe on anterior chaetigers (versus equal superior and inferior lobes); and 6) shorter serrations on the blade of heterogomph falcigers on neuropodia (Fig. 17D–H, Table 2; Hutchings et al. 1991: 253–254, fig. 8a–c; Park and Kim 2017: 257, figs. 3A, 4C, 5F, table 4). Perinereis pangcahae sp. nov. can be distinguished from P. helleri by having: 1) greater number of paragnaths on areas III and IV (22–27 and 19–33 versus 11–20 and 10–19, respectively); 2) chevron-shaped bar on area VI (versus long straight bar); 3) ɔc-shaped ridge pattern of areas VI–V–VI (versus u-shaped ridge pattern); 4) dorsal cirri attached 1/3 to base of dorsal ligule on anterior chaetigers (versus medially attached to dorsal ligule); 5) the center and proximal lobes of dorsal ligule with one large irregular-shaped glandular mass on posterior chaetigers (versus absent); and 6) neuroacicular ligule with predominant inferior lobe on anterior chaetigers (versus equal superior and inferior lobes) (Fig. 17D–H, Table 2; Hutchings et al. 1991: 255, fig. 9a–c; Park and Kim 2017: 255–256, 258, figs. 3B, 2, 4E, 5C2, table 4). The differences between P. pangcahae sp. nov. and four other new species of the 1A group described in the present study are discussed below. page 35 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan Perinereis pseudocultrifera sp. nov. (Fig. 18, Table 2) urn:lsid:zoobank.org:act:FCC51AFF-F9B8-4607-AABAD34AF9B7A5CB Material examined: Holotype, NSNM 8748-127, Wuchi Harbor (23°13.70'N, 121°25.08'E), habitat type: SRHB, 7 July 2015. Paratype: 1 specimen, NMNS 8748-128, Bisha Harbor (25°08.75'N, 121°47.17'E), habitat type: SRHB, 20 July 2016. Non-types: 1 specimen, NMNS 8748-129, Wuchi Harbor (23°13.70'N, 121°25.08'E), habitat type: SRHB, 7 July 2015; 1 specimen, NMNS 8748-130, Wuchi Harbor (23°13.70'N, 121°25.08'E), habitat type: SRHB, 5 October 2015; 1 specimen, NMNS 8748-131, Bisha Harbor (25°08.75'N, 121°47.17'E), habitat type: SRHB, 20 July 2016. Etymology: The name is derived from the fusion of the Greek “pseudȇs” (false, deceptive) and the Latin “cultrifera”, referring to that the species shows a series of affinities to Perinereis cultrifera. Description: Based on holotype (NSNM 8748127, complete; atoke), paratypes (NMNS 8748-128, complete; atoke) and non-types (NMNS 8748-129–131, incomplete specimens; all atoke): Body length 48.0 (24.5) mm with 86 (68) chaetigers, chaetiger 10 width 1.9 (1.0–2.3, n = 4) mm, excluding parapodia; beige in alcohol (Fig. 18A, B). Prostomium wider than long, lateral antennae antero-lateral, shorter than palps, palpophores globose, palpostyles spheroid. Four pairs of tentacular cirri, longest one reaching chaetiger 3 (2–4, n = 4). Two pairs of eyes, in trapezoidal arrangement. Tentacular belt about 1.3x (1.1–1.3x, n = 4) longer than chaetiger 1. Pharynx with dark brown jaws, each with 6–7 (5–8, n = 4) teeth; paragnath pattern: I = 2 (1–3, n = 4) (same sample size on remaining areas), in cluster; II = 9 (9–11) (left), 9 (8–11) (right), in 2 (2–3) oblique rows; III = 8 (11–14) (center region with 6 (7–11) cones, in 2 (3) in oval-shaped patch; 2 lateral regions, each with 1 (0–4) cones; IV = 16 (15–21) (left), 17 (12–25) (right), in 3 (3–4) oblique rows, without bars; V = 0; VI = 1 (left), 1 (right), short bars; VII–VIII = 31 (30–35) cones, in 2 rows. Ridge pattern of areas VI–V– VI, λ-shaped (Fig. 18A, B, Table 2). Dorsal cirri digitiform, medially attached to dorsal ligule, about 0.7–0.8x as long as dorsal ligule on anterior to mid-body chaetigers, attached 2/3 to base of dorsal ligule on posterior chaetigers, about 0.4x as long as dorsal ligule on posterior chaetigers (Fig. 18C–E, Table 2). Dorsal ligule subconical throughout, about 2.9x longer than median ligule on anterior chaetigers, about 1.7x longer than median ligule on mid-body chaetigers, about 2.3x longer than median ligule on posterior chaetigers; center and proximal lobes with one large irregular-shaped glandular mass on mid-body to posterior chaetigers (Fig. 18C–E, Table 2). Notopodial prechaetal lobe present throughout (Fig. 18C–E, Table 2). Median ligule conical, about as long as neuroacicular ligule on anterior chaetigers, subconical on midbody to posterior chaetigers, about 1.4x longer than neuroacicular ligule on mid-body chaetigers, about 1.6x as long as neuroacicular ligule on posterior chaetigers (Fig. 18C–E). Neuroacicular ligule with predominant inferior lobe, about 0.5x as long as ventral ligule on anterior chaetigers, inferior and superior lobes subequal in length on mid-body to posterior chaetigers, about 0.6–0.7x as long as ventral ligule. Neuropodial postchaetal lobe absent. Ventral ligule subconical throughout. Ventral cirri mid-ventrally attached to ventral edge of parapodia, about 0.8x as long as ventral ligule on anterior to midbody chaetigers, about 0.9x as long as ventral ligule on posterior chaetigers (Fig. 18C–E). Notochaetae present from chaetiger 3 to posterior chaetigers, homogomph spinigers present throughout. Supra-acicular fascicle of neuropodia: homogomph spinigers and short-bladed heterogomph falcigers with serrations present throughout. Subacicular fascicle of neuropodia: short-bladed heterogomph falcigers with serrations and heterogomph spinigers present throughout (Fig. 18F–I, Table 2). Pygidium with anus crenulated; anal cirri cirriform, as long as last 2 chaetigers. Type locality: Wuchi Harbor, Taichung City, Taiwan. Distribution: Known only from type locality and Bisha Harbor, New Taipei City, Taiwan. Remarks: Perinereis pseudocultrifera sp. nov. can be included in group 1A of the genus based on the presence of one bar-shaped paragnath on area VI of the pharynx and not greatly expanded dorsal ligule on posterior chaetigers (Hutchings et al. 1991: 271) (Fig. 18A, E, Table 2). Of the seven species in this group reported from East and South Asia (see the Remarks section in P. houbihuensis sp. nov. for the name of these seven species), only P. cultrifera (Grube, 1840) is similar to P. pseudocultrifera sp. nov. in terms of having similar paragnath patterns on areas I, II, III, IV, VI and VII–VIII, similar dorsal notopodial morphology, and neuropodial heterogomph spinigers present on chaetigers of all body regions (Fig. 18A– C, F, G, Table 2; Hutchings et al. 1991: 250, 253, 255; Park and Kim 2017: 255–258, tables 2, 4). However, P. pseudocultrifera sp. nov. can be distinguished from P. cultrifera by having: 1) no paragnaths on area V (versus 2–5); 2) notopodial prechaetal lobe present on chaetigers of all body regions (versus present only on page 36 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan Fig. 18. Perinereis pseudocultrifera sp. nov.; holotype (NSNM 8748-127): A, anterior body region, dorsal view; B, anterior body region, dorsal view; C, right parapodium, anterior view, chaetiger 10; D, right parapodium, anterior view, chaetiger 46; E, right parapodium, anterior view, chaetiger 76; F, chaetae of chaetiger 10; G, chaetae of chaetiger 76; H, I, neuropodial heterogomph falciger, chaetiger 76. Abbreviations: HeF = heterogomph falciger; HeS = heterogomph spiniger; NoPL = notopodial prechaetal lobe. Scale bars: A, B = 0.5 mm; C–E = 0.2 mm; F, G = 0.05 mm; H, I = 0.02 mm. page 37 of 57 Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan anterior chaetigers); 3) conical median ligule on anterior chaetigers (versus subconical); 4) neuroacicular ligule with predominant inferior lobe on anterior chaetigers (versus subequal inferior and superior lobes); and 5) short-bladed neuropodial heterogomph falcigers (versus medium-sized blade) (Fig. 18A–I, Table 2; Hutchings et al. 1991: 253, fig. 8a–c; Park and Kim 2017: 258, table 4). The differences between P. pseudocultrifera sp. nov. and four other new species of group 1A described in the present study are discussed below. Interestingly, P. pseudocultrifera sp. nov. and P. floridana (Ehlers, 1868) are the only two Perinereis species found in subtidal fouling community on cement pier surface of Wuchi Harbor, Taichung City, west-central Taiwan. Morphologically, P. pseudocultrifera sp. nov. is somewhat similar to P. floridana but can be readily distinguished from the latter species by having: 1) lateral teeth on area III (versus absent); 2) no conical paragnaths on area V (versus 1 conical paragnath); and 3) notopodial prechaetal lobe present on chaetigers of all body regions (versus absent) (Figs. 5A–G, 18A–E, Table 2; de LeónGonzález and Solís-Weiss 1998: 684, figs. 6A–E, 7A–E; de León-González and Goethel 2013: 7). Perinereis qiguensis sp. nov. (Fig. 19, Table 3) urn:lsid:zoobank.org:act:AF8AB19D-BFE4-4328-9696EE7294590FEA Material examined: Holotype, NSNM 8748-132, Qigu (23°04.70'N, 120°02.46'E), habitat type: ISSB, 20 January 1993. Etymology: The name is derived from the Qigu lagoon, where the worm was collected. Description: Holotype: atoke, complete, body length 39.0 mm with 96 chaetigers, chaetiger 10 width 1.5 mm, excluding parapodia; beige in alcohol (Fig. 19A). Prostomium wider than long, lateral antennae antero-lateral, longer palps, palpophores globose, palpostyles spheroid. Four pairs of tentacular cirri, longest one reaching chaetiger 6. Two pairs of eyes, in trapezoidal arrangement. Tentacular belt about 1.3x longer than chaetiger 1. Pharynx with dark brown jaws, each with 5 teeth; paragnath pattern: I = 5, in nearly transverse row; II = 21 (left), 23 (right), in 2–3 oblique rows; III = 30 (center region with 16 cones, in 4 transverse rows; 2 lateral regions, each with 3 cones, in longitudinal line); IV = 22 (left), 23 (right), in 3–4 oblique rows, without bars; V = 3, in transverse row; VI = 7 (2 long bars at both end; 5 short bars in between long bars) (left), 6 (2 long bars, 1 outermost, 1 next to outermost; 4 short bars with 3 in between long bars, 1 outermost) (right), in shallow u-shaped line; VII–VIII = 36, in 2–3 rows. Ridge pattern of areas VI–V–VI, λ-shaped (Fig. 19B, Table 3). Dorsal cirri digitiform, attached 1/3 to base of dorsal ligule on anterior to mid-body chaetigers, about 0.6–0.7x as long as dorsal ligule, medially attached to dorsal ligule on posterior chaetigers, about 0.5x as long as dorsal ligule on posterior chaetigers (Fig. 19C–E, Table 3). Dorsal ligule subconical, not greatly elongated throughout, about 2.0–2.2x longer median ligule on anterior to posterior chaetigers, center lobe of dorsal ligule with one oval-shaped glandular mass on posterior chaetigers (Fig. 19C–E). Notopodial prechaetal lobe present throughout (Fig. 19C–E, Table 3). Median ligule conical throughout, about 1.2x longer than neuroacicular ligule on anterior chaetigers, about 1.5–1.6x longer than neuroacicular ligule on midbody to posterior chaetigers (Fig. 19C–E). Neuroacicular ligule with predominant inferior lobe on anterior chaetigers, inferior and superior lobes subequal in length on mid-body to posterior chaetigers, about 0.7x as long as ventral ligule on anterior to midbody chaetigers, about as long as ventral ligule on posterior chaetigers. Neuropodial postchaetal lobe absent. Ventral ligule subconical throughout. Ventral cirri basally attached to ventral edge, about 0.8–0.9x as long as ventral ligule on anterior to mid-body chaetigers, about as long as ventral ligule on posterior chaetigers (Fig. 19C–E). Notochaetae present from chaetiger 3 to posterior chaetigers, homogomph spinigers present throughout. Supra-acicular fascicle of neuropodia: homogomph spinigers and short-bladed heterogomph falcigers with serrations present throughout. Subacicular fascicle of neuropodia: short-bladed and medium-sized blade heterogomph falcigers with serrations present throughout, heterogomph spinigers present only on midbody to posterior chaetigers (Fig. 19F–J, Table 3). Pygidium with anus crenulated; anal cirri cirriform, as long as last 6 chaetigers. Type locality: Qigu Lagoon, Tainan City, Taiwan. Distribution: Known only from type locality. Remarks: Perinereis qiguensis sp. nov. belongs to group 3A, as well as the Perinereis nuntia species group, by having an arc of 6–7 bar-shaped paragnaths on area VI of the pharynx and not greatly expanded notopodial dorsal ligule on posterior chaetigers (Fig. 19B, E, Table 3; Hutchings et al. 1991: 271; Wilson and Glasby 1993: 259; Glasby and Hsieh 2006: 558; Villalobos-Guerrero 2019: 468). Of the 20 known species in this species group recognized by VillalobosGuerrero (2019), only P. mictodonta (Marenzeller, 1879) and P. wilsoni Glasby and Hsieh, 2006 are somewhat similar to P. qiguensis sp. nov., because all have uneven bar-shaped paragnaths and five to six page 38 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan Fig. 19. Perinereis qiguensis sp. nov.; holotype (NSNM 8748-132): A, anterior body region, dorsal view; B, close-up of areas V, VI and VIII of the pharynx; C, right parapodium, anterior view, chaetiger 10; D, right parapodium, anterior view, chaetiger 35; E, right parapodium, anterior view, chaetiger 72; F, neuropodial heterogomph falciger, chaetiger 35; G, neuropodial heterogomph spiniger, chaetiger 35; H, I, neuropodial heterogomph falciger, chaetiger 72; J, neuropodial heterogomph spiniger, chaetiger 72. Abbreviation: NoPL = notopodial prechaetal lobe. Scale bars: A, B = 0.5 mm; C–E = 0.2 mm; F, G = 0.05 mm; H, I = 0.02 mm. page 39 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan paragnaths on area VI, as well as lateral paragnaths on area III (Figs. 15B, 19B; Glasby and Hsieh 2006: 562, table 2; Villalobos-Guerrero 2019: 489). However, P. qiguensis sp. nov. can be distinguished from P. mictodonta by having: 1) λ-shaped ridge pattern of areas VI–V–VI (versus χ-shaped pattern); 2) smaller length ratio of dorsal cirri to dorsal ligule on anterior and posterior chaetigers (about 0.6 and about 0.5 versus 1.07 and 1.04, respectively); 3) one large, ovalshaped glandular mass in the center lobe of dorsal ligule on posterior chaetigers (versus one irregularshaped glandular mass in each of the center and proximal lobes); 4) notopodial prechaetal lobe present on chaetigers of all body regions (versus absent); and 5) neuropodial heterogomph spinigers present only on mid-body to posterior chaetigers (versus present on all chaetigers) (Fig. 15B–F, 19B–I, Table 3; Glasby and Hsieh 2006: 560–561, fig. 5C–D; Villalobos-Guerrero 2019: 489). Perinereis qiguensis sp. nov. differs from P. wilsoni by having: 1) more paragnaths on area I (5 versus 1–3); 2) λ-shaped ridge pattern of areas VI–V–VI (versus χ-shaped ridge pattern); 3) smaller length ratio of dorsal cirri to dorsal ligule on anterior and posterior chaetigers (about 0.6 and about 0.5 versus 1.43 and 2.35, respectively); 4) one large, oval-shaped glandular mass in the center lobe of dorsal ligule on posterior chaetigers (versus one irregular-shaped glandular mass in each of the center and proximal lobes); and 5) neuropodial heterogomph spinigers present only on mid-body to posterior chaetigers (versus present on all chaetigers) (Fig. 19B–I, Table 3; Glasby and Hsieh 2006: 560–561, 572, figs. 5C–D, 10C–D, table 2; Villalobos-Guerrero 2019: 489). The differences between P. qiguensis sp. nov. and eight other new species of group 3A described in the present study are discussed below. Perinereis taitungensis sp. nov. (Fig. 20, Table 2) urn:lsid:zoobank.org:act:95B3090A-8AC9-4E1E-8568871D6F9770FE Material examined: Holotype, NSNM 8748-133, Jialulan (22°48.36'N, 121°11.92'E), habitat type: IRHB, 19 August 2012. Paratype: 1 specimen, NSNM 8748134, Jihuei (23°06.87'N, 121°24.21'E), habitat type: IRHB, 27 March 2014. Etymology: The name is derived from the name of the county, Taitung, eastern Taiwan, where with the worm was collected. Description: Based on holotype (NSNM 8748133, complete; atoke) and paratype (NSNM 8748134, incomplete; atoke): body length 84.0 mm with 139 chaetigers, chaetiger 10 width 3.3 mm, excluding parapodia; beige with brown spots on dorsal body edge and base of dorsal ligule on mid-body to posterior chaetigers in alcohol (Fig. 20A, D, E). Prostomium wider than long, lateral antennae antero-lateral, shorter than palps, palpophores globose, palpostyles spheroid. Four pairs of tentacular cirri, longest one reaching chaetiger 2. Two pairs of eyes, in trapezoidal arrangement. Tentacular belt about 1.4x longer than chaetiger 1. Pharynx with dark brown jaws, each with 3 teeth; paragnath pattern: I = 2 (2), in longitudinal line; II = 6 (6) (left), 11 (8) (right), in 2–3 (2) oblique rows; III = 19 (13) (center region with 14 (9) cones, in 4 transverse rows; 2 lateral regions, each with 2 (2) or 3 (2) cones, in longitudinal line); IV = 25 (19) (left), 26 (24) (right), in 4 oblique rows; V = 3 (3 large cone + 1 small cone), in triangle (small cone posteriorly to 3 large cones); VI = 1 (0) (left), 1 (1) (right), shield-shaped bars; VII–VIII = 28 (30), in 3 rows. Ridge pattern of areas VI–V–VI, ɔc-shaped (Fig. 20B, C, Table 2). Dorsal cirri digitiform, attached 1/3 to base of dorsal ligule in anterior chaetigers, about 0.8x as long as dorsal ligule, attached 2/3 to base of dorsal ligule in mid-body to posterior chaetigers, about 0.4x as long as dorsal ligule (Fig. 20F–H, Table 2). Dorsal ligule subconical throughout, as long as median ligule on anterior to mid-body chaetigers, about 1.9x longer than median ligule on posterior chaetigers; center and proximal lobes of dorsal ligule each with orange brownish, triangle-shaped, glandular mass on mid-body to posterior chaetigers (Fig. 20F–H). Notopodial prechaetal lobe present only on mid-body chaetigers (Fig. 20F–H, Table 2). Median ligule subconical throughout, slightly longer than neuroacicular ligule throughout (Fig. 20F– H). Neuroacicular ligule with predominant inferior lobe on anterior to mid-body chaetigers, subequal inferior and superior lobes on posterior chaetigers, slightly shorter than ventral ligule on anterior to midbody chaetigers, as long as ventral ligule on posterior chaetigers. Neuropodial postchaetal lobe absent. Ventral ligule subconical throughout. Ventral cirri digitiform, mid-ventrally attached to ventral edge of parapodia, about 0.7x as long as ventral ligule throughout (Fig. 20F–H). Notochaetae present from chaetiger 3 to posterior chaetigers, homogomph spinigers present throughout. Supra-acicular fascicle of neuropodia: homogomph spinigers and short-bladed heterogomph falcigers with serrations present throughout. Subacicular fascicle of neuropodia: medium-sized blade heterogomph falcigers with serrations present throughout, heterogomph spinigers present on mid-body to posterior chaetigers (Fig. 20I–L, Table 2). page 40 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan Pygidium with anus crenulated; anal cirri cirriform, as long as last 3 chaetigers. Type locality: Jialulan, Taitung County, Taiwan. Distribution: Known only from type locality and Jihuei, Taitung County, Taiwan. Remarks: Perinereis taitungensis sp. nov. has one bar-shaped paragnath on area VI and not greatly expanded notopodial dorsal ligule on posterior chaetigers, suggesting it can be categorized in group 1A (Hutchings et al. 1991: 271) (Fig. 20B, H, Table 2). Of the seven species in this group reported from East and Southeast Asia (see the Remarks section in P. houbihuensis sp. nov. for the name of these seven species), only P. cultrifera (Grube, 1840), P. euiini Park and Kim, 2017, and P. helleri (Grube, 1878) is similar to P. taitungensis sp. nov., which all have 3 Fig. 20. Perinereis taitungensis sp. nov.; A, B, D–L, holotype (NSNM 8748-133); C, paratype (NSNM 8748-134): A, anterior body region, dorsal view; B, C, close-up of areas V, VI and VIII of the pharynx; D, close-up of mid-body segments; E, close-up of posterior body segments; F, right parapodium, anterior view, chaetiger 10; G, right parapodium, anterior view, chaetiger 50; H, right parapodium, anterior view, chaetiger 95; I, closeup of neuropodial chaetae, chaetiger 10; J, close-up of neuropodial chaetae, chaetiger 50; K, close-up of neuropodial chaetae, chaetiger 95; L, neuropodial heterogomph falciger, chaetiger 95. Abbreviation: NoPL = notopodial prechaetal lobe. Scale bars: A, B = 0.5 mm; C–E = 0.2 mm; F, G = 0.05 mm; H, I, = 0.02 mm. page 41 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan versus 14); 2) greater dorsal cirri to dorsal ligule length ratio on anterior and posterior chaetigers (about 0.8 and 0.3 versus 0.3 and 0.2 (based on measurements from pl. 8, fig. 4 in Horst 1889), respectively); 3) the distal, center and proximal lobes of dorsal ligule each with one irregular-shaped glandular masses on mid-body to posterior chaetigers (versus absent); and 4) anal opening not surrounded by papillae (versus surrounded by papillae) (Fig. 23B–D, Table 4; Horst 1889: 168–170, pl. 8, figs. 4, 6). Perinereis wanlitongensis sp. nov. differs from P. nigropunctata by having: 1) no prechaetal lobe on chaetigers of all body regions (versus present on chaetigers of all body regions); 2) greater length ratio of dorsal ligule to median ligule on posterior chaetigers (4.3 versus 3.3); and 3) one irregular-shaped glandular mass in each of the distal, center and proximal lobes of dorsal ligule on posterior chaetigers (versus 1 in the center lobe) (Fig. 23C, D, Table 4). Perinereis kebalanae sp. nov. and P. wanlitongensis sp. nov. are the two only new species described in the present study which can be categorized in group 1B (Table 4). Perinereis kebalanae sp. nov. can be distinguished from P. wanlitongensis sp. nov. by having: 1) more paragnaths on areas II, III and IV (19–25, 30–35 and 50–54 versus 11–13, 20 and 22–27, respectively); 2) no lateral teeth on area III (versus present); 3) bar-shaped paragnaths on area IV (versus absent); 4) fewer number of paragnaths on area V (1 versus 3–4); 5) u-shaped ridge pattern of areas VI–V– VI (versus λ-shaped ridge pattern), no glandular masses in the lobes of dorsal ligule (versus 3 glandular masses); 6) smaller length ratio of dorsal ligule to median ligule on posterior chaetigers (3.5 versus 4.2); and 7) heterogomph spinigers on anterior chaetigers (versus absent on anterior chaetigers) (Table 4). Perinereis wilsoni Glasby and Hsieh, 2006 (Fig. 24, Table 3) Perinereis wilsoni Glasby and Hsieh 2006: 570–573, fig. 10 (for complete synonym). Material examined: 2 specimens, NSNM 8748184–185, Aodi (25°02.97'N, 121°55.78'E), habitat type: IRHB, 23 March 1993; 1 specimen, NSNM 8748-186, Magang (25°00.81'N, 122°00.13'E), habitat type: IRHB, 6 March 2001; 2 specimens, NSNM 8748-187–188, Linshanbi (25°16.99'N, 121°30.59'E), habitat type: IRHB, 20 November 2003; 1 specimen, NSNM 8748-189, Dali (24°57.62'N, 121°55.27'E), habitat type: IRHB, 23 November 2003; 2 specimens, NSNM 8748-190–191, Longdongwan (25°07.02'N, 121°54.98'E), habitat type: SRHB, 7 March 2004; 4 specimens, NSNM 8748-192–195, Shimen (25°17.85'N, 121°34.14'E), habitat type: IRHB, 14–16 March 2004; 1 specimen, NSNM 8748-196, Hsinchu (24°51.00'N, 120°55.48'E), habitat type: SRHB, 18 July 2016. Description: Based on 5 complete specimens (NSNM 8748-186–187, NSNM 8748-190–191, NSNM 8748-193, all atoke) and 8 incomplete specimens (NSNM 8748-184–185, NSNM 8748-188, NSNM 8748-189, NSNM 8748-192, NSNM 8748-194–196, all atoke): Body length 29.0–66.5 (n = 5) mm with 73–110 (n = 5) chaetigers, chaetiger10 width 2.0–5.1 (n = 13) mm, excluding parapodia; beige in alcohol (Fig. 24A, B). Prostomium wider than long, lateral antennae antero-lateral, shorter than palps, palpophores globose, palpostyles spheroid. Four pairs of tentacular cirri, longest one reaching chaetiger 4–11 (n = 12). Two pairs of eyes, in trapezoidal arrangement. Tentacular belt about 1.1–1.6x (n = 13) longer than chaetiger 1. Pharynx with dark brown jaws, each with 5–6 (n = 13) teeth; paragnath pattern: I = 1–3 cones, mostly 2 (n = 13, same sample size on following areas), in longitudinal line; II = 6–15 cones (left), 6–15 cones (right), in 2–3 oblique rows; III = 14–25 cones (center region with 10–23 cones, in 3–4 transverse rows; 2 lateral regions, each with 1–2 or 1–3 cones; IV = 13–34 cones (left), 19–34 cones (right), in 3–4 oblique rows, without bars; V = 1–3 (mostly 1 or 2, one case of 3); VI = 4–7 uneven-length bars, inner and outer-most longest (one case of one additional cone) (left), 4–7 uneven-length bars, inner and outer-most longest (right), in transverse row; VII– VIII = 14–36, in 2–3 rows. Ridge pattern of areas VI–V– VI, χ-shaped (Fig. 24A, B, Table 3). Dorsal cirri digitiform, attached 1/3 to base of dorsal ligule on anterior chaetigers, about 0.9x as long as dorsal ligule, medially attached dorsal ligule on midbody to posterior chaetigers, about 0.5–0.7x as long as dorsal ligule on mid-body to posterior chaetigers (Fig. 24C–E, Table 3). Dorsal ligule subconical throughout, about 2.0x longer than median ligule throughout; proximal lobe of dorsal ligule with two irregular-shaped glandular masses on posterior chaetigers (Fig. 24C–E). Notopodial prechaetal lobe absent (Table 3). Median ligule subconical throughout, about 1.2x longer than neuroacicular ligule on anterior chaetigers, about as long as neuroacicular ligule on mid-body to posterior chaetigers (Fig. 24C–E). Neuroacicular ligule with prominent inferior lobe on anterior chaetigers, about 0.5x as long as ventral ligule, inferior and superior lobes subequal in length on mid-body to posterior chaetigers, about as long as ventral ligule. Neuropodial postchaetal lobe absent. Ventral cirri digitiform, mid-ventrally attached to ventral edge of parapodia throughout, about 0.6–0.7x as page 48 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan long as ventral ligule (Fig. 24C–E). Notochaetae present from chaetiger 3 to posterior chaetigers, homogomph spinigers present throughout. Supra-acicular fascicle of neuropodia: homogomph spinigers and medium-sized blade heterogomph falcigers with serrations present throughout. Subacicular fascicle of neuropodia: medium-sized blade heterogomph falcigers with serrations and heterogomph spinigers present throughout (Fig. 24F, Table 3). Pygidium with anus crenulated; anal cirri cirriform, as long as last 5–9 (n = 5) chaetigers (Table 3). Distribution: Japan, Korea Strait (South Korea), South China Sea and Yellow Sea (China), Taiwan (Glasby and Hsieh 2006). Remarks: Morphology of examined specimens in the present study agrees with original description of P. wilsoni Glasby and Hsieh, 2006 (Fig. 24A–F, Table 3; Glasby and Hsieh 2006: 572, fig. 10A–F). All examined specimens of P. wilsoni in the present study were mostly collected from reef habitats on coasts of northern Taiwan, which agrees with the northerly distribution of this species in Taiwan reported by Glasby and Hsieh (2006: 555, fig. 1). Perinereis yehliuensis sp. nov. (Fig. 25, Table 3) urn:lsid:zoobank.org:act:D9D90DCA-1FEB-434D-A573F3C49EAED0DB Material examined: Holotype, NSNM 8748-197, Yehliu (25°12.46'N, 120°41.56'E), habitat type: IRHB, coll. H.-T. Hung, 13 April 1999. Etymology: The name is derived from the name of nearby village, Yehliu, where the worm was collected. Description: Holotype, epitoke, without posterior end, remaining body length 45.0 mm with 78 chaetigers, chaetiger 10 width 2.0 mm, excluding parapodia; beige in alcohol (Fig. 25A, B). Prostomium wider than long, lateral antennae antero-lateral, longer than palps, palpophores globose, palpostyles spheroid. Four pairs of Fig. 24. Perinereis wilsoni Glasby and Hsieh, 2006; A, B (NSNM 8748-184); C–F (NSNM 8748-193): A, anterior body region, dorsal view; B, close-up of areas V, VI and VIII of the pharynx; C, left parapodium, anterior view, chaetiger 9; D, left parapodium, anterior view, chaetiger 40; E, left parapodium, anterior view, chaetiger 80; F, neuropodial chaetae, chaetiger 9. Abbreviations: HeF = heterogomph falciger; HeS = heterogomph spiniger. Scale bars: A, B = 1.0 mm; C–E = 0.2 mm; F = 0.02 mm. page 49 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan tentacular cirri, longest one reaching chaetiger 5. Two pairs of eyes, in trapezoidal arrangement. Tentacular belt about 1.3x longer than chaetiger 1. Pharynx with dark brown jaws, each with 2 (damaged?) or 5 teeth; paragnath pattern: I = 3, in triangle; II = 5 (damaged?), 21, in 3 oblique rows; III = 27 (center region with 21 cones, in 4 transverse rows; 2 lateral regions, each with 3 cones, in longitudinal line); IV = 31 (left), 34 (right), in 4 oblique rows; without bars; V = 5, in loosely cluster; VI = 6 (2 long bars (innermost and 2nd outermost), 4 short bars (median and outermost) (left), 8 (2 long bars (innermost and 2nd outermost), 6 short bars (median and outermost) (right), in shallow u-shaped line; VII–VIII = 23, in 2–3 rows. Ridge pattern of areas VI–V–VI, ɔc-shaped (Fig. 25C, Table 3). Pre-natatory region: Dorsal cirri robust with filament distally on chaetigers 1 to 7, basally attached to dorsal ligule, about 1.2x longer than dorsal ligule, digitiform on chaetiger 8 to 16, medially attached to dorsal ligule, about 0.8x as long as dorsal ligule (Fig. 25D–F). Dorsal ligule subconical, about as long as median ligule. Notopodial prechaetal lobe absent. Fig. 25. Perinereis yehliuensis sp. nov.; holotype (NSNM 8748-197): A, whole animal; B, anterior body region, dorsal view; C, close-up of areas V and VI of the pharynx, black arrow points fall off bars of right area VI; D, right parapodium, anterior view, chaetiger 10; E, right parapodium, anterior view, chaetiger 35; F, right parapodium, anterior view, chaetiger 57; G, neuropodial chaetae, chaetiger 10; H, natatory chaetae and neuropodial heterogomph chaetae, chaetiger 30; I, natatory chaetae, neuropodial heterogomph falcigers and heterogomph spinigers, chaetiger 57. Abbreviation: NoPL = notopodial prechaetal lobe. Scale bars: A = 1.0 mm; B = 0.5 mm; C = 0.1 mm; D–F = 0.2 mm; G–I = 0.02 mm. page 50 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan Median ligule subconical. Neuroacicular ligule with predominant inferior lobe. Neuropodial postchaetal lobe absent. Ventral ligule subconical. Ventral cirri robust on chaetigers 1 to 7, becoming digitiform along chaetigers 8 to 16, mid-ventrally attached to ventral edge of parapodia, as long as ventral ligule (Fig. 25D). Notochaetae homogomph spinigers. Supra-acicular fascicle of neuropodia: homogomph spinigers and medium-size blade heterogomph falcigers with serrations. Subacicular fascicle of neuropodia: homogomph spinigers and medium-size blade heterogomph falcigers with narrow serrations (Fig. 25G, Table 3). Natatory region: Dorsal cirri digitiform, medially attached to dorsal ligule, about 0.5–0.6x as long as dorsal ligule. Dorsal cirrus lobe present from chaetiger 17, becoming kidney-shaped lamellae from on mid-body chaetigers, reduced progressively in size thereafter (Fig. 25E, F). Dorsal ligule subconical, about 1.4x longer than median ligule. Notopodial prechaetal lobe absent. Median ligule subconical, as long as neuroacicular ligule. Neuroacicular ligule with predominant inferior lobe, inferior and superior lobes subequal in length on posterior half of mid-body to posterior chaetigers, as long as ventral ligule. Neuropodial postchaetal lobe present. Ventral ligule subconical. Ventral cirri midventrally attached to ventral edge of parapodia, about 0.5–0.7x as long as ventral ligule with irregular-shaped dorsal and ventral lobes on anterior-half of natatory chaetigers, gradually reduced in size thereafter (Fig. 25E, F). Notochaetae present from chaetiger 3 to posterior chaetigers, homogomph spinigers present. Supra-acicular fascicle of neuropodia: homogomph spinigers present, heterogomph falcigers absent. Subacicular fascicle of neuropodia: medium-size blade heterogomph falcigers with narrow serrations present, natatory chaetae present, homogomph spinigers present only on posterior chaetigers (Fig. 25H, I, Table 3). Type locality: Yehliu Township, New Taipei City, Taiwan. Distribution: Known only from the type locality. Remarks: With the presence of an arc of 6–8 barshaped paragnaths on area VI of the pharynx and not greatly expanded notopodial dorsal ligule on posterior chaetigers, P. yehliuensis sp. nov. belongs to group 3A and the Perinereis nuntia group (Fig. 25C, F, Table 3; Hutchings et al. 1991: 271; Wilson and Glasby 1993: 259; Glasby and Hsieh 2006: 558; Villalobos-Guerrero 2019: 468). Of the 20 known species of the Perinereis nuntia group recognized by Villalobos-Guerrero (2019), P. yehliuensis sp. nov. is similar to P. shikueii Glasby and Hsieh, 2006 in terms of having similar number of paragnaths on areas I to III and VI, lateral teeth on area III, and ɔc-shaped ridge pattern of areas VI–V–VI (Table 3; Glasby and Hsieh 2006: 562, 568, fig. 8A– D, table 2; Villalobos-Guerrero 2019: 489). However, P. yehliuensis sp. nov. can be distinguished from P. shikueii by having: 1) more paragnaths on area V (5, in loosely cluster versus mostly 3, in shallow triangle); 2) uneven-length bars on area VI (versus even-length bars); 3) fewer number of paragnaths on areas VII–VIII (23 versus 34–52); 4) smaller length ratio of dorsal cirri to dorsal ligule on both anterior and posterior chaetigers (0.7 and 0.5 versus 0.90–1.08 and 0.69–1.63); and 5) no glandular masses in the center lobe of dorsal ligule on posterior chaetigers (versus present) (Fig. 25C, D, F, Table 3; Glasby and Hsieh 2006: 562, 568, fig. 8A–D, table 2). The differences between P. yehliuensis sp. nov. and eight other new species of the 3A group described in the present study are discussed below. Perinereis yufuensis sp. nov. (Fig. 26, Table 3) urn:lsid:zoobank.org:act:8D97DDFE-4BD9-4039-ADA9B139E8574478 Material examined: Holotype, NSNM 8748-198, Yufu (22°20.90'N, 120°23.38'E), habitat type: ISSB, Liuqiu, 11 May 2000. Etymology: The name is derived from the name of nearby village, Yufu, where the worm was collected. Description: Holotype, atoke, complete, body length 72.5 mm with 142 chaetigers, chaetiger 10 width 1.9 mm, excluding parapodia; beige in alcohol (Fig. 26A). Prostomium wider than long, lateral antennae antero-lateral, shorter than palps, palpophores globose, palpostyles spheroid. Four pairs of tentacular cirri, longest one reaching chaetiger 5. Two pairs of eyes, in trapezoidal arrangement. Tentacular belt about 1.3x longer than chaetiger 1. Pharynx with dark brown jaws, each with 4 teeth; paragnath pattern: I = 2, in longitudinal line; II = 9 (left), 7 (right), in cluster; III = 10 (center region with 8 cones, in 3 transverse rows; 2 lateral regions, each with 1 cone); IV = 18 (left), 16 (right), in 3–4 oblique rows, without bars; V = 3, in slightly arced transverse row; VI = 7 (1 dark colored shield-shaped bar (innermost), 5 light to dark colored uneven-length short bars, 1 long bar (outermost) (left), 6 (2 light to dark colored shield-shaped bars (innermost and outermost), 4 light colored short bars) (right), in u-shaped line; VII–VIII = 28, in 3 rows. Ridge pattern of areas VI–V–VI, ɔc-shaped (Fig. 26B, Table 3). Dorsal cirri digitiform, medially attached to dorsal ligule throughout, about 0.5x as long as dorsal ligule on anterior chaetigers, about 0.3x as long as dorsal ligule on mid-body to posterior chaetigers (Fig. 26C–E, Table 3). Dorsal ligule subconical throughout, about 1.9x page 51 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan longer than median ligule on anterior chaetigers, about 1.5x longer than median chaetigers on mid-body to posterior chaetigers; proximal lobe of dorsal ligule with one large, oval-shaped glandular mass on posterior chaetigers (Fig. 26C–E). Notopodial prechaetal lobe absent (Table 3). Median ligule subconical throughout, about 1.2x longer than neuroacicular ligule, about 1.6x and 1.3x longer than neuroacicular ligule on mid-body and posterior chaetigers, respectively (Fig. 26C–E). Neuroacicular ligule with predominant inferior lobe on anterior chaetigers, inferior and superior lobes Fig. 26. Perinereis yufuensis sp. nov.; holotype (NSNM 8748-198): A, anterior body region, dorsal view; B, close-up of areas V, VI and VIII of the pharynx; C, right parapodium, anterior view, chaetiger 9; D, right parapodium, anterior view, chaetiger 51; E, right parapodium, anterior view, chaetiger 100; F, chaetal pattern of chaetiger 51; G, chaetal pattern of chaetiger 100; H, close-up of neuropodial chaetae, chaetiger 100. Scale bars: A = 0.5 mm; B = 0.1 mm; C–E = 0.2 mm; F, G = 0.1 mm; H = 0.02 mm. page 52 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan subequal in length on mid-body to posterior chaetigers, about 0.6x as long as ventral ligule throughout. Neuropodial postchaetal lobe absent. Ventral ligule subconical throughout. Ventral cirri mid-ventrally attached to ventral edge of parapodia, about 0.9x as long as ventral ligule on anterior chaetigers, about 0.6x as long as ventral ligule on mid-body chaetigers, about 0.8x as long as ventral ligule on posterior chaetigers (Fig. 26C–E). Notochaetae present from chaetiger 3 to posterior chaetigers, homogomph spinigers present throughout. Supra-acicular fascicle of neuropodia: homogomph spinigers and medium-size blade heterogomph falcigers with serrations present throughout. Subacicular fascicle of neuropodia: medium-size blade heterogomph falcigers with serrations present throughout, heterogomph spinigers present only on posterior chaetigers (Fig. 26F– H, Table 3). Pygidium with anus crenulated; anal cirri cirriform, as long as last 3 chaetigers. Type locality: Yufu, Liuqiu Township, Pingtung County, Taiwan. Distribution: Known only from the type locality. Remarks: Perinereis yufuensis sp. nov. belongs to group 3A and the Perinereis nuntia species group by having an arc of 6–7 bar-shaped paragnaths on area VI of the pharynx and not elongated notopodial dorsal ligule on posterior chaetigers (Fig. 26B, E, Table 3; Hutchings et al. 1991: 271; Wilson and Glasby 1993: 259; Glasby and Hsieh 2006: 558; Villalobos-Guerrero 2019: 468). Of the 20 known species of the Perinereis nuntia group recognized by Villalobos-Guerrero (2019), P. yufuensis sp. nov. is similar to P. shikueii Glasby and Hsieh, 2006 in terms of having similar number of paragnaths on areas I to V and VI, lateral teeth on area III, and ɔc-shaped ridge pattern of areas VI–V–VI (Fig. 26B, Table 3; Glasby and Hsieh 2006: 562, 568, fig. 8A– D, table 2; Villalobos-Guerrero 2019: 489). However, P. yufuensis sp. nov. can be distinguished from P. shikueii by having: 1) less paragnaths on areas II, III, IV and VII–VIII (7–9, 10, 16–18, 28 versus 17–19, 18–29, 21–35 and 34–52, respectively); 2) uneven-length bars on area VI (versus even-length bars); 3) smaller length ratio of dorsal cirri to dorsal ligule on both anterior and posterior chaetigers (0.5 and 0.3 versus 0.90–1.08 and 0.69–1.63); 4) neuropodial heterogomph spinigers present only on posterior chaetigers (versus present on chaetigers of all body regions) (Fig. 26C–E, Table 3; Glasby and Hsieh 2006: 562, 568, fig. 8A–D, table 2). Key to Perinereis species reported from Taiwan 1. Area VI with 1 bar ...................................................................... 2 - Area VI with 2 or more bars ..................................................... 14 2. Dorsal ligule not greatly expanded on posterior chaetigers ....... 3 - Dorsal ligule greatly expanded on posterior chaetigers ........... 10 3. Area III with lateral teeth ........................................................... 4 - Area III without lateral teeth ...................................................... 8 4. Area V with 3 cones ................................................................... 5 - Area V without cones ........................ P. pseudocutrifera sp. nov. 5. Notopodia with prechaetal lobe .................................................. 6 - Notopodia without prechaetal lobe ............................................ 7 6. Notopodia prechaetal lobe present only on anterior chaetigers, neuropodial heterogomph spinigers present on chaetigers of all body regions ...................................... P. cultrifera (Grube, 1840) - Notopodia prechaetal lobe present only on mid-body chaetigers, neuropodial heterogomph spinigers present only on mid-body to posterior chaetigers ................................. P. taitungensis sp. nov. 7. Area VI with long straight bar, u-shaped ridge pattern of areas VI–V–VI ................................................. P. helleri (Grube, 1878) - Area VI with chevron-shaped bar, ɔc-shaped ridge pattern of areas VI–V–VI .......................................... P. pangcahae sp. nov. 8. Area V with one cone ................................................................. 9 - Area V with 4–16 cones ................ P. longdongwanensis sp. nov. 9. Areas VI–V–VI with λ-shaped ridge pattern ................................ ............................................................ P. floridana (Ehlers, 1868) - Areas VI–V–VI with χ-shaped ridge pattern ................................. ................................................................ P. houbihuensis sp. nov. 10. Area III with lateral teeth, area IV without bars ....................... 11 - Area III without later teeth, area IV with or without bars ........ 12 11. Notopodia prechaetal lobe present; dorsal ligule to median ligule length ratio about 3.3 on posterior chaetigers ............................... ...................................................... P. nigropunctata (Horst, 1889) - Notopodia prechaetal lobe absent; dorsal ligule to median ligule length ratio about 4.3 on posterior chaetigers ............................... ............................................................. P. wanlitongensis sp. nov. 12. Area IV with bars ..................................................................... 13 - Area IV without bars ...................... P. euiini Park and Kim, 2017 13. Area VI with cones; neuropodia without heterogomph spinigers ................................................ P. amblyodonta (Schmarda, 1868) - Area VI without cones; neuropodial with heterogomph spinigers on mid-body to posterior chaetigers ........... P. kebalanae sp. nov. 14. Area VI with 2 bars .................................................................. 15 - Area VI with 3 or more bars ..................................................... 17 15. Area VI with 2 very short bars; neuropodial heterogomph falcigers with long blade ............... P. aibuhitensis (Grube, 1878) - Area VI with 2 long straight bars; neuropodial heterogomph falcigers with medium-sized blade ........................................... 16 16. Area IV with more than 39 cones; areas VII–VIII with more than 57 cones .......................................... P. vancaurica (Ehlers, 1868) - Area IV with fewer than 37 cones; areas VII–VIII with fewer than 57 cones ............................... P. singaporiensis Grube, 1878 17. Dorsal ligule not greatly expanded on posterior chaetigers ..... 18 - Dorsal ligule greatly expanded on posterior chaetigers ........... 29 18. Area III with cones, areas VII–VIII with more than 13 cones ...... ................................................................................................... 19 - Area III without cones, areas VII–VIII with less than 13 cones ... ........................................................................ P. tubicola sp. nov. 19. Area III with lateral teeth ......................................................... 20 - Area III without lateral teeth ................... P. kaomeiensis sp. nov. 20. Area VI with 3 bars ................................ P. hsinchuensis sp. nov. - Area VI with more than 3 bars ................................................. 21 21. Areas VI–V–VI with λ-shaped ridge pattern ........................... 22 - Areas VI–V–VI with ɔc-shaped or χ-shaped ridge pattern ...... 23 22. Area V with 3 cones, Area III with 30 cones ................................ ...................................................................... P. qiguensis sp. nov. - Area V without cones, Area III with 17 cones .............................. .................................................................... P. ludaoensis sp. nov. page 53 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan 23. Areas VI–V–VI with ɔc-shaped ............................................... 24 - Areas VI–V–VI with χ-shaped ridge pattern ............................ 28 24. Area V with 1 cone; neuropodia without heterogomph spinigers on chaetigers of all body regions .................. P. daxiensis sp. nov. - Area V with 3 or more cones; neuropodia with heterogomph spinigers at least on posterior chaetigers .................................. 25 25. Neuropodia with heterogomph spinigers on anterior chaetigers ... ................................................................................................... 26 - Neuropodia without heterogomph spinigers on anterior chaetigers ................................................................................................... 27 26. Area VII–VIII with more than 33 cones; dorsal ligule center lobe with one large oval-shaped glandular mass on posterior chaetigers .............................. P. shikueii Glasby and Hsieh, 2006 - Area VII–VIII with less than 24 cones; dorsal ligule center lobe without glandular mass on posterior chaetigers ............................ .................................................................... P. yehliuensis sp. nov. 27. Area III with 17 cones; neuropodia with heterogomph spinigers on mid-body to posterior chaetigers .......... P. liuqiuensis sp. nov. - Area III with 10 cones; neuropodia with heterogomph spinigers only on posterior chaetigers ......................... P. yufuensis sp. nov. 28. Dorsal cirri to dorsal ligule length ratio about 1.5 anteriorly, increasing to 2.0–3.0 posteriorly ................................................... ................................................ P. wilsoni Glasby and Hsieh, 2006 - Dorsal cirri to dorsal ligule length ratio about 1.0 throughout (except last few chaetigers) ... P. mictodonta (Marenzeller, 1879) 29. Area V with 10 small and many minute cones .............................. .................................................................. P. fugangensis sp. nov. - Area V with 1 large and many minute cones ................................ ...................................................... P. neocaledonica Pruvot, 1930 DISCUSSION The present study supports the usage of paragnath patterns (excluding paragnath pattern of area III in some species), ridge patterns of area V–VI– VI, morphology of parapodia, types of heterogomph falcigers, and the composition and distribution of subacicular fascicle neurochaetae of the body regions for properly identifying Perinereis species in previous reports (Hutchings et al. 1991; Wilson and Glasby 1993; Bakken and Wilson 2005; Glasby and Hsieh 2006; Conde-Vela 2018; Villalobos-Guerrero 2019; Villalobos-Guerrero et al. 2021). Discrepancy of paragnath pattern on area III of the pharynx in P. vancaurica between reports from Indian Ocean and Australia (i.e., Ehlers 1904: 25; Hutchings et al. 1991) and from other geographic regions (i.e., Fauvel 1953: 206, fig. 105g; Wu 1967: 71, Imajima 1972: 86, fig. 23b; Wu et al. 1981: 176, fig. 111B) raises questions on the stability of this character for identifying species. A similar case was also observed by Hutchings et al. (1991: 253), who noted about half of P. cultrifera specimens examined in their study have lateral teeth on area III. The five new Perinereis species of group 1A described in the present study can be divided into two groups based on the absence or presence of lateral teeth on area III of the pharynx. Perinereis taitungensis sp. nov., P. pangcahae sp. nov., and P. pseudocultrifera sp. nov. have lateral teeth on area III, whereas P. houbihuensis sp. nov. and P. longdongwanensis sp. nov. have no lateral teeth. The former group can be further distinguished from the latter group by having 3 or no paragnaths on area V, comparing to that of 1 or 4–16 in the latter group (see Table 2). In the former group, P. pseudocultrifera sp. nov. is readily differentiated from P. pangcahae sp. nov. and P. taitungensis sp. nov. by the absence of paragnaths on area V and glandular masses in the center or proximal lobe of dorsal ligule on posterior chaetigers (versus 3 and 1 or 2, respectively), λ-shaped ridge pattern of areas VI–V–VI (versus ɔcshaped ridge pattern), and the presence of notopodial prechaetal lobe on chaetigers of all body regions (versus absent and present only on mid-body chaetigers, respectively) (Table 2). Perinereis taitungensis sp. nov. differs from P. pangcahae sp. nov. by having notopodial prechaetal lobe on mid-body chaetigers (versus absent on chaetigers of all body regions), one triangle-shaped glandular mass in each of the center and proximal lobes of the dorsal ligule on posterior chaetigers (versus 1 large irregular-shaped glandular mass in the center and proximal lobes), and neuropodial heterogomph spinigers absent on anterior chaetigers (versus present on chaetigers of all body regions) (Table 2). In the latter group, P. houbihuensis sp. nov. differs from P. longdongwanensis sp. nov. by having less paragnaths on all areas of the pharynx, χ-shaped ridge pattern of areas VI–V–VI (versus λ-shaped ridge pattern), greater length ratio of dorsal ligule to median ligule on posterior chaetigers (2.5 versus 1.8), one irregularshaped glandular mass in the center and proximal lobes of dorsal ligule on posterior chaetigers (versus absent), and neuropodial heterogomph spinigers present only on posterior chaetigers (versus present on chaetigers of all body regions) (Table 2). Of the nine new Perinereis species of group 3A described in the present study, P. tubicola sp. nov. can be distinguished from the other eight species by having only few numbers of paragnaths on areas II and IV, no paragnaths on area III (versus at least 10), and u-shaped ridge pattern of areas VI–V–VI (Table 3). The absence of neuropodial heterogomph spinigers on chaetigers of all body regions in P. daxiensis sp. nov. is a unique feature that is not seen in the other eight species (Table 3). The remaining seven species can be divided into two groups based on ridge pattern of areas VI–V–VI. Perinereis ludaoensis sp. nov. and P. qiguensis sp. nov. have λ-shaped ridge pattern, whereas the other four species have ɔc-shaped ridge pattern (Table 3). Perinereis ludaoensis sp. nov. differs from P. qiguensis sp. nov. by having less paragnaths on areas II, III and VII–VIII (11, 17 and 18 versus 21–23, 30 and 36, respectively), no paragnaths on area V (versus 3), page 54 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan greater number of paragnaths on area VI (9–11 versus 6–7), no notopodial prechaetal lobe (versus present on anterior chaetigers), and no glandular masses in the center lobe of dorsal ligule on posterior chaetigers (versus one glandular mass) (Table 3). Of the five species with ɔc-shaped ridge pattern of areas VI–V–VI, P. kaomeiensis sp. nov. can be easily distinguished from the other four species by having more paragnaths on areas I, III and VII–VIII (9, 54 and 52 versus less than 4, 28 and 38, respectively), no lateral teeth on area III (versus present), and notopodial prechaetal lobe present on pre-natatory chaetigers (versus absent) (Table 3). Perinereis hsinchuensis sp. nov. can be distinguished from P. liuqiuensis sp. nov., P. yehliuensis sp. nov., and P. yufuensis sp. nov. by having fewest number of paragnaths on area VI (3 versus exceed 5) and no neuropodial heterogomph spinigers on posterior chaetigers (versus present on posterior chaetigers) (Table 3). Perinereis yehliuensis sp. nov. can be differentiated from P. liuqiuensis sp. nov. and P. yufuensis sp. nov. by having greater number of paragnaths on areas III, IV and V (27, 31–33 and 5 versus less than 18, 22 and 4, respectively), no glandular masses in the center lobe of dorsal ligule on posterior chaetigers (versus one glandular mass), and neuropodial heterogomph spinigers present on anterior chaetigers (versus absent on anterior chaetigers) (Table 3). Finally, P. liuqiuensis sp. nov. differs from P. yufuensis sp. nov. by having greater number of paragnaths on areas III and VI (17 and 9 versus 10 and 6–7, respectively) and neuropodial heterogomph spinigers present on mid-body to posterior chaetigers (versus present only on posterior chaetigers) (Table 3). Glasby and Hsieh (2006: 558) added the absence of notopodial prechaetal lobe as an additional character in the diagnosis of the Perinereis nuntia species group proposed by Wilson and Glasby (1993: 259). Of the nine new species of this species group described in the present study, seven agree with this diagnosis of which have no notopodial prechaetal lobe (see Table 3). However, P. kaomeiensis sp. nov. and P. qiguensis sp. nov. have notopodial prechaetal lobe present on anterior or pre-natatory chaetigers (Figs. 10D, 19C–E, Table 3). Similar case was noted by Villalobos-Guerrero (2019: 488) who acknowledged the presence of notopodial prechaetal lobe in P. maindroni. However, VillalobosGuerrero (2019: 468) did not incorporate the abovementioned character into his emended diagnosis of the species group. The author also makes no attempt herein to emend diagnosis of this body part for this species group. Counting 12 previously reported species and 18 newly reported species (17 new species and one occurrence reconfirmed species) in the present study, Taiwan is now hosting a total of 30 Perinereis species, making the island with the highest regional species richness of the genus in the world, surpassing that of 17 species reported from Australia (Hutchings et al. 1991; Wilson and Glasby 1993; Glasby et al. 2013). CONCLUSIONS A review on the biodiversity of the genus Perinereis from Taiwan has been conducted in the present study. Results of this study document 24 Perinereis species from this geographic area. Of these 24 species, 17 are new to science, and they are: Perinereis daxiensis sp. nov., P. fugangensis sp. nov., P. kaomeiensis sp. nov., P. kebalanae sp. nov., P. houbihuensis sp. nov., P. hsinchuensis sp. nov., P. liuqiuensis sp. nov., P. longdongwanensis sp. nov., P. ludaoensis sp. nov., P. pangcahae sp. nov., P. pseudocultrifera sp. nov., P. qiguensis sp. nov., P. taitungensis sp. nov., P. tubicola sp. nov., P. wanlitongensis sp. nov., P. yehliuensis sp. nov., and P. yufuensis sp. nov. The record of P. cultrifera (Grube, 1840), originally described from the Mediterranean Sea, is confirmed for Taiwan. The remaining six are species previously reported from Taiwan, which are: Perinereis aibuhitensis (Grube, 1878), P. floridana (Ehlers, 1868), P. mictodonta (Marenzeller, 1879), P. nigropunctata (Horst, 1889), P. vancaurica (Ehlers, 1868), and P. wilsoni Glasby & Hsieh, 2006. The cumulated number of Perinereis species for Taiwan reaches 30 with the present study, making this island by far with the highest regional species richness of the genus in the world. The generic diagnosis has been partially amended to include the presence of neuropodial homogomph spinigers found in the subacicular fascicle of P. longdongwanensis sp. nov. Acknowledgments: This study was partially supported by the Ministry of Science and Technology, Republic of China (MOST 108-2621-B-005-004-MY3). I thank Mr. J.-H. Chang, H.-T. Hong, K.-R. Li, Y.-H. Li, Y.-W. Tzeng, and J.-H. Zhu for their assistance in field collections. I also thank the National Museum of Natural Science, Republic of China, for loaning specimens. Valuable comments of Dr. Sergio I. SalazarVallejo on the manuscript are greatly appreciated. Authors’ contributions: PWH responses for field collections, examining the specimens, writing the full text, and making all the figures and tables of this manuscript. Competing interests: PWH declares that he has no page 55 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan conflict of interests. Availability of data and materials: All type specimens were deposited in the National Museum of Science and Nature, Taiwan. Consent for publication: Not applicable. Ethics approval consent to participate: Not applicable. REFERENCES Arias A, Richter A, Anadón N, Glasby CJ. 2013. Revealing polychaetes invasion patterns: Identification, reproduction and potential risks of the Korean ragworm, Perinereis linea (Treadwell), in the Western Mediterranean. Est Coast Shelf Sci 131:117–128. doi:10.1016/j.ecss.2013.08.017. Augener H. 1913. Polychaeta I. Errantia. pp. 65–304. In: Michaelsen W, Hartmeyer R (eds) Die Fauna Südwest-Australiens. Ergebnisse der Hamburger südwest-australischen Forschungsreise 1905. Gustav Fischer, Jena 4:65–304, plates II–III. Augener H. 1922. Australische Polychaeten des Hamburger Zoologischen Museums. Arch Naturgesch 87, Abt. A, H. 7:1–37, 33 text-figs. Bakken T, Wilson RS. 2005. Phylogeny of nereidids (Polychaeta, Nereididae) with paragnaths. Zool Scr 34:507–547. doi:10.1111/ j.1463-6409.2005.00200.x. Bakken T, Glasby CJ, Santos CSG, Wilson RS. 2018. Nereididae Blainville, 1818. In: Westheide W, Purschke G, Böggemann M (eds) Handbook of Zoology. A Natural History of the Phyla of the Animal Kingdom, Annelida: Polychaetes. De Gruyter, Ösnabruck. Bhatt YM, Bal DV. 1966. An account of the polychaetous annelids of Bombay. J Univ Bombay 32:24–51. Chen CA, Chen CP, Fan TY, Yu JK, Hsieh HL. 2002. Nucleotide sequences of ribosomal internal transcribed spacers and their utility in distinguishing closely related Perinereis polychaetes (Annelida; Polychaeta; Nereididae). Mar Biotech 4:17–29. doi:10.1007/s10126-001-0069-3. Conde-Vela VM. 2018. New species of Pseudonereis Kinberg, 1865 (Polychaeta: Nereididae) from the Atlantic Ocean, and a review of paragnath morphology and methodology. Zootaxa 4471:245– 278. doi:10.11646/zootaxa.4471.2.2. Day JH. 1967. A Monograph of the Polychaeta of Southern Africa. Part I Errantia. British Museum of Natural History Publication, London. de Blainville H. 1818. Mémoire sur la classe des Sétipodes, partie des Vers à sang rouge de M. Cuvier, et des Annélides de M. de Lamarck. Bull Soc philomath, Paris 1818:78–85. de León-González JA, Goethel C. 2013. A new species of Perinereis (Polychaeta, Nereididae) from Florida, USA, with a key to all Perinereis from the American continent. ZooKeys 312:1–11. doi:10.3897/zookeys.312.4535. de León-González JA, Solís-Weiss V. 1998. The genus Perinereis (Polychaeta: Nereididae) from Mexican littoral waters, including the description of three new species and the redescriptions of P. anderssoni and P. elenacasoae. Pro Biol Soc Wash 111:674–693. Ehlers E. 1868. Die Borstenwiirmer (Annelida Chaetopoda) nach systematischen und anatomischen untersuchungen dargestellt. Leipzig, Wilhelm Engelmann. xxiv + 748 pp., 24 pls (pp. 1–268, 11 pls published in 1864). Ehlers E. 1904. Neuseelandische Anneliden. Abh. Königl Ges Wiss Göttingen, Math-Phys Kl 3:1–80, 9 pls. Fauchald K, Ganados-Barba A, Solis-Weiss V. 2009. Polychaeta (Annelida) of the Gulf of Mexico. pp. 751–788. In: Felder DL, and Camp DK (eds) Gulf of Mexico. Origins, Wates and Biota. Volume 1. Biodiversity. Texas A&M University Press, College Station, Texas, USA. Fauvel P. 1915. Polychètes pelagiques nouvelles des Campagnes de la Princesse-Alice (note préliminaire). Bull Inst Oceanogr 305:1– 11. Fauvel P. 1932. Annelida Polychaeta of the Indian Museum, Calcutta. Mem Indian Mus, Calcutta 12:1–262, 9 pls. Fauvel P. 1943. Deux polychètes nouvelles. Bull Mus Natl Hist Nat, Paris. Série 2 15:200–202. Fauvel P. 1953. Annelida Polychaeta. The Fauna of India including Pakistan, Ceylon, Burma and Malaya. The Indian Press Ltd, Allahabad. Glasby CJ. 2015. Nereididae (Annelida: Phyllodocida) of Lizard Island, Great Barrier Reef, Australia. Zootaxa 4019:207–239. doi:10.11646/zootaxa.4019.1.11. Glasby CJ, Hsieh H-L. 2006. New species and new records of the Perinereis nuntia species group (Nereididae: Polychaeta) from Taiwan and other Indo-West Pacific shores. Zool Stud 45:553– 577. Glasby CJ, Wei Nu-Wei V, Gibb KS. 2013. Cryptic species of Nereididae (Annelida: Polychaeta) on Australian coral reefs. Invertebr Syst 27:245–264. doi:10.1071/IS12031. Glasby CJ, Lee Y-L, Hsueh P-W. 2016. Marine Annelida (excluding clitellates and siboglinids) from the South China Sea. Raffles Bull Zool, Suppl No. 34:178–234. Gravier C. 1901. Contribution a l'etude des Annelides polychetes de la mer Rouge. Nouv Ann Mus Hist nat Paris, ser 4 3:147–268. Grube AE. 1840. Actinien, Echinodermen und Würmer des Adriatischenund Mittelmeers nach eigenen Sammlungen beschrieben. J.H. Bon, Königsberg, Germany. Grube AE. 1866. Beschreibungen neuer von der Novara-Expedition mitgebrachter Anneliden und einer neuen Landplanarie. Verh k-k zool-bot Ges 16:173–184. Grube AE. 1867. Anneliden. Reise der Osterreichischen Fregatte Novara um die Erde in den Jahren 1857, 1858 und 1859. Zoologischer Theil 2:1–46, 4 pls. Grube AE. 1878. Annulata Semperiana. Beiträge zur Kenntniss der Annelidenfauna der Philippinen. Mem Acad Sci St Petersb 25:1–300. Hartmann-Schröder G. 1979. Die Polychaeten der tropischen Nordwestküste Australiens (zwischen Derby im Norden und Port Hedland im Süden). Teil 2. In: Hartmann-Schröder, G. and Hartmann, G. Zur Kenntnis des Eulitorals der australischen Küsten unter besonder Berücksichtigung der Polychaeten und Ostracoden. (Teil 2 und Teil 3). Mitt zool Mus 76:77–218. Horst R. 1889. Contributions towards the knowledge of the Annelida Polychaeta. Not Leyden Mus 11:38–45, pl. 3. Horst R. 1919. Three new Nereis-species from the Dutch East Indies. Zool Meded, Leiden 5:59–64. Horst R. 1924. Polychaeta errantia of the Siboga Expedition. Part III. Nereidae and Hesionidae. Siboga-Expeditie Uitkomsten Zoologisch, Bonatisch, Oceanographisch Geologisch gebied verzameld Nederlandsch Oost-Indië 1899-1900 24:145–198. Hsueh P-W. 2018. First records of Composetia, Eunereis and Nectoneanthes (Annelida: Nereididae) from Taiwan, with descriptions of two new species. Zootaxa 4531:211–224. doi:10.11646/zootaxa.4531.2.3. Hsueh P-W. 2019a. Neanthes (Annelida: Nereididae) from Taiwanese waters, with description of seven new species and one new species page 56 of 57Zoological Studies 63:39 (2024) © 2024 Academia Sinica, Taiwan record. Zootaxa 4554:173–198. doi:10.11646/zootaxa.4554.1.5. Hsueh P-W. 2019b. Two new species of nereidids (Annelida, Polychaeta) from Taiwan. Zootaxa 4652:544–556. doi:10.11646/ zootaxa.4652.3.10. Hsueh P-W. 2020. New species of Nereis (Annelida, Polychaeta, Nereididae) from Taiwanese waters. Zootaxa 4802:1–31. doi:10.11646/zootaxa.4802.1.1. Hsueh P-W. 2021. New species and record of Pseudonereis (Annelida, Polychaeta, Nereididae) from Taiwan. Zootaxa 4996:492–512. doi:10.11646/zootaxa.4996.3.4. Hsueh P-W. 2022. Three new polychaete species of Platynereis (Annelida, Polychaeta, Nereididae) from Taiwan. Zool Stud 61:30. doi:10.6620/ZS.2022.61-30. Hutchings PA, Reid A, Wilson RS. 1991. Perinereis (Polychaeta, Nereididae) from Perinereis (Polychaeta, Nereididae) from Australia, with redescriptions of six additional species. Rec Aust Mus 43:241–274. doi:10.3853/j.0067-1975.43.1991.47. Hylleberg J, Nateewathana A, Bussarawit S. 1986. Polychaetes of Thailand. Nereidae (Part 1); Perinereis and Pseudonereis with notes on species of commercial value. Phuket Mar Biol Center Res Bull 43:1–22. Imajima M. 1972. Review of the annelid worms of the family Nereidae of Japan, with descriptions of five new species or subspecies. Bull Nat Sci Mus, Tokyo 15:37–153. Izuka A. 1912. The Errantiate Polychaeta of Japan. J Coll Sci Tokyo Univ 30:1–262, 24 pls. Kinberg JGH. 1865. Annulata nova. [Continuatio.]. Öfvers Kongl Vetensk-Akad Förh 22:167–179. Kott P. 1951. Nereidae and Eunicidae of south western Australia; also notes on the ecology of Western Australian limestone reefs. J Proc Royal Soc Western Australia 35:85–130. Marenzeller E von. 1879. Sudjapanische Anneliden I. (Amphinomea, Aphroditea, Lycoridea, Phyllodocea, Hesionea, Syllidea, Eunicea, Glycerea, Sternaspidea, Chaetopterea, Cirratulea, Amphictenea.). Kaiserl Akad Wiss Wien, Math Naturwiss Kl, Denkschr 41:109–154, 6 pls. Monro CCA. 1931a. Polychaeta, Oligochaeta, Echiuroidea and Sipunculoidea. Scientific Reports of the Great Barrier Reef (Qld) Expedition 1928-29. Sci Rep British Mus (Nat Hist) 4:1–37. Monro CCA. 1931b. On a collection of Polychaeta in the Raffles Museum, Singapore. Bull Raffles Mus, Singapore, Straits Settlements 5:33–46. Monro CCA. 1933. On a collection of Polychaeta from Dry Tortugas, Florida. Ann Mag Nat Hist Ser 10 12:244–269. Monro CCA. 1934. On a collection of polychaeta from the coast of China. Ann Mag nat Hist ser 10 13:353–380. Park T, Kim W. 2017. Description of a new species for Asian populations of the “Cosmopolitan” Perinereis cultrifera (Annelida: Nereididae). Zool Sci 34:252–260. doi:10.2108/ zs160154. Pruvot G. 1930. Annélides polychètes de Nouvelle-Calédonie recueillies par M. François, avec une introduction et des notes de Pierre Fauvel. Arch Zool Exp Gén 70:1–94, 3 pls. Russell E. 1962. Some nereid polychaetes from Queensland. Univ Queensland Papers, Depart Zool 2:1–12. Salazar-Vallejo SI, Jiménez-Cueto MS. 1996–1997. Neréididos (Polychaeta) del Caribe Mexicano con una clave para las especies del Gran Caribe. Rev Biol Trop 44/45:361–377. Salazar-Vallejo SI, de León-González JA, Conde-Vela VM. 2021. Revision of the species confused with “Nereis falsa” de Quatrefages, 1866 (Annelida, Nereididae). Europ J Tax 779:1– 70. doi:10.5852/ejt.2021.779.1579. Southern R. 1921. Polychaeta of the Chilka Lake and also of fresh and brackish waters in other parts of India. Mem Indian Mus, Calcutta 5:563–659, pls. 19–31. Sun R, Yang D. 2004. Annelida. Polychaeta II. Nereidida (= Nereimorpha). Nereididae, Syllidae, Hesionidae, Pilargidae, Nephtyidae. In: Huo, C. and Zhao, G. (eds) Fauna Sinica, Invertebrata. Science Press, Beijing. (in Chinese with English abstract) Tosuji H, Nishinosono K, Hsieh HL, Glasby CJ, Sakaguchi T, Sato M. 2019. Molecular evidence of cryptic species diversity in the Perinereis nuntia species group (Annelida: Nereididae) with first records of P. nuntia and P. shikueii in southern Japan. Plankton Benthos Res 14:287–302. doi:10.3800/pbr.14.287. Treadwell AL. 1936. Polychaetous annelids from Amoy, China. Proc US Nat Mus 83:261–279. doi:10.5479/si.00963801.83-2984.261. Villalobos-Guerrero TF. 2019. Redescription of two over-looked species of the Perinereis nuntia complex and morphological delimitation of P. nuntia (Savigny in Lamarck, 1818) from the Red Sea (Annelida, Nereididae). Zoosystema 41:465–496. doi:10.5252/zoosystema2019v41a24. Villalobos-Guerrero TF, Bakken T. 2018. Revision of the Alitta virens species complex (Annelida: Nereididae) from the North Pacific Ocean. Zootaxa 4483:201–257. doi:10.11646/zootaxa.4483.2.1. Villalobos-Guerrero TF, Park T, Idris I. 2021. Review of some Perinereis Kinberg, 1865 (Annelida: Nereididae) Group 2 sensu Hutchings, Reid & Wilson, 1991 from the Eastern and South-eastern Asian seas. J Mar Biol Assoc U K 101:279–307. doi:10.1017/S0025315421000126. Wilson RS, Glasby CJ. 1993. A revision of the Perinereis nuntia species group (Polychaeta: Nereididae). Rec Aust Mus 45:253– 277. doi:10.3853/j.0067-1975.45.1993.23. Wu BL, Sun R, Yang DJ. 1981. The Nereidae (Polychaetous annelids) of the Chinese coast. China Ocean Press, Beijing. (in Chinese with English abstract) Wu BL, Sun R, Yang DJ. 1985. The Nereidae (Polychaetous annelids) of the Chinese coast. China Ocean Press, Beijing and SpringerVerlag, Berlin, Germany. Wu S-K. 1967. The nereid worms of Taiwan. Bull Inst Zool, Acad Sinica 6:47–76. page 57 of 57Zoological Studies 63:39 (2024)