Three new species of Velia (Cesavelia) Koçak & Kemal, 2010 (Hemiptera, Heteroptera, Veliidae) from China

313 Three new species of Velia (Cesavelia) Koçak & Kemal, 2010 (Hemiptera, Heteroptera, Veliidae) from China Siying Fu1, Zezhong Jin1, Zhen Ye1 1 Institute of Entomology, College of Life Sciences, Nankai University, Tianjin, 300071, China Corresponding author: Zhen Ye ([email protected]) Copyright: © Siying Fu et al. This is an open access article distributed under terms of the Creative Commons Attribution License (Attribution 4.0 International – CC BY 4.0). Research Article Abstract Velia (Cesavelia) lii sp. nov. and Velia (Cesavelia) motuoensis sp. nov. from Xizang Province, China, as well as Velia (Cesavelia) yiliangensis sp. nov. from Yunnan Province, China, are described. Photographs illustrating the habitus in dorsal and lateral views, male metafemora, genitalic structures, and habitats, as well as a key to the species of Velia (Cesavelia) are provided, along with an updated distribution map of the subgenus. Key words: Hengduan Mountains, Himalayas, identification key, new species, riffle bugs, taxonomy, Veliidae, water striders Introduction The genus Velia Latreille, 1804, is currently divided into three subgenera, each characterized by allopatric distributions. The subgenus Velia Latreille, 1804, comprises a single extant species, which is distributed across the western Mediterranean (Tamanini 1947; Andersen 1995; Berchi et al. 2018). The subgenus Plesiovelia Tamanini, 1955, includes 28 taxa (23 species and 5 subspecies), distributed from western Europe to northwestern India, with an extension into northern Africa (Andersen 1981, 1995; Tran et al. 2009; Berchi et al. 2018; Jin et al. 2023). The subgenus Cesavelia Koçak & Kemal, 2010, contains 11 species distributed across the Oriental Region, including northern India, Nepal, central and southern China, and northern Vietnam (Andersen 1981; J. Polhemus and D. Polhemus, 1999; D. Polhemus and J. Polhemus 2003; Tran et al. 2009; Koçak and Kemal 2010; Basu et al. 2013). Cesavelia exhibits high species diversity along the southern slopes of the Himalayas and the Hengduan Mountains (Tran et al. 2009; Jin et al. 2023). Ongoing exploration of the region has led to the discovery and description of additional new species. In the present study, we describe three new species: Velia (Cesavelia) lii sp. nov. and Velia (Cesavelia) motuoensis sp. nov. from Xizang Province, China, and Velia (Cesavelia) yiliangensis sp. nov. from Yunnan Province, China. These findings contribute further insight into the diversity patterns of Velia in this region. Additionally, this paper provides photographs of the habitus in dorsal and lateral views, male metafemora, genitalic structures, and habitats of new species described in this study, along with a distribution map of described species of Cesavelia to date. Academic editor: Jader Oliveira Received: 17 April 2025 Accepted: 18 August 2025 Published: 3 October 2025 ZooBank: https://zoobank. org/72A88792-371F-4288-92DE97541FCBD62B Citation: Fu S, Jin Z, Ye Z (2025) Three new species of Velia (Cesavelia) Koçak & Kemal, 2010 (Hemiptera, Heteroptera, Veliidae) from China. ZooKeys 1254: 313–329. https://doi. org/10.3897/zookeys.1254.156152 ZooKeys 1254: 313–329 (2025) DOI: 10.3897/zookeys.1254.156152 314 ZooKeys 1254: 313–329 (2025), DOI: 10.3897/zookeys.1254.156152 Siying Fu et al.: New species of subgenus Velia (Cesavelia) from China Material and methods All the specimens examined in this study are deposited in the Institute of Entomology, College of Life Sciences, Nankai University, Tianjin, China (NKUM). All measurements are given in millimeters (mm). The illustrations of specimens in dorsal view and structural details were captured using a Nikon SMZ1000 stereomicroscope equipped with a computer-controlled SPOT RT digital camera and Helicon software (Helicon Remote ver. 3.9.12 W and Helicon Focus ver. 7.7.5). The skeletal elements of genital segments were dissected after being macerated with 5% KOH. The photographs of the dissected male genital segments immersed in glycerin were made using an OLYMPUS BX53 microscope equipped with a computer-controlled Canon OLYMPUS DP72 digital camera and cellSens Standard ver. 1.6 software. The recording points in the map refer to the distribution information from the literature (Tran et al. 2009; Jin et al. 2023). Taxonomic accounts Family Veliidae Brullé, 1836 Subfamily Veliinae Brullé, 1836 Genus Velia Latreille, 1804 Subgenus Cesavelia Koçak & Kemal, 2010 Diagnosis (modified from Andersen 1981, and Tran et al. 2009). Antennal segment I distinctly longer than head width across eyes (except Velia anderseni Tran, Zettel & Buzzetti, 2009, which is almost equal to head width). Mesotarsus less than 2/3 mesotibia length. Metatibia distinctly longer than metafemur. Metafemur of male slender or moderately incrassate (in V. anderseni) and more heavily armed than in female on flexor side. Metatibia with scattered erect setae. In males, abdominal segment VIII relatively large, dorsal hind margin medially emarginated; proctiger plate-shaped, apically broadened; parameres prominent, strongly curved. In females, proctiger plate-shaped, covering gonocoxae and genital opening. Key to the species of Velia (Cesavelia) Note. Apterous forms; updated based on the “Key to the species of Velia (Haldwania) in the Oriental Region” in Tran et al. 2009). Hitherto, apterous forms of V. championi and V. steelei are still unknown (Tran et al. 2009). 1 Tarsal segment II of hind leg subequal or shorter than segment III. Metafemur of male, width/length ratio ≈ 0.27 (fig. 5 in Tran et al. 2009) ......... V. anderseni – Tarsal segment II of hind leg distinctly longer than segment III (1.1–1.6 times). Metafemur of male, width/length ratio < 0.2 (Fig. 3) .....................2 2 Sides of sternites black and with wide yellow connexival stripes almost restricted to sternites III–V (macropterous morph; fig. 45 in Tran et al. 2009). Extensor sides of meso-and metatibiae with erect setae longer than tibia width (Tran et al. 2009) ....................................................................V. steelei – Sides of sternites without such color pattern. Extensor sides of meso-and metatibiae with erect setae shorter than tibia width (Tran et al. 2009) .....3 315 ZooKeys 1254: 313–329 (2025), DOI: 10.3897/zookeys.1254.156152 Siying Fu et al.: New species of subgenus Velia (Cesavelia) from China 3 Sides of abdomen predominantly orange, black marks restricted to sternites II–IV (fig. 43 in Tran et al. 2009) ........................................ V. championi – Sides of abdomen predominantly black or dark brown (Tran et al. 2009) 4 4 Male ................................................................................................................5 – Female..........................................................................................................15 5 Proctiger strongly modified, with large dilations on posterior part (figs 18–20 in Tran et al. 2009 and fig. 7a, b in Jin et al. 2023) ..........................6 – Proctiger only slightly modified or not modified, with small dilations on postero-lateral part (Fig. 4g, i, k; figs 14–16 in Tran et al. 2009; fig. 13 in Basu et al. 2013 and fig. 7c, d in Jin et al. 2023) .........................................9 6 Hind margin of proctiger bisinuate, sides upcurved with pointed wings (fig. 18 in Tran et al. 2009) ....................................................... V. laticaudata – Hind margin of proctiger not bisinuate (straight, nearly straight, or convex) .................................................................................................................7 7 Hind margin of proctiger almost straight, lateral margin straight (fig. 20 in Tran et al. 2009) ............................................................................V. yunnana – Hind margin of proctiger convex or curved, lateral margin curved ............8 8 Hind margin of proctiger slightly curved (fig. 19 in Tran et al. 2009 and fig. 7b in Jin et al. 2023) ...........................................................V. longiconnexiva – Hind margin of proctiger broadly rounded (fig. 7b in Jin et al. 2023) ....V. bui 9 Apex of paramere moderately rounded (figs 25, 26 in Tran et al. 2009 and figs 15, 16 in Basu et al. 2013). Endosoma: accessory sclerite well-sclerotized, ventral sclerites visible (fig. 37 in Tran et al. 2009 and fig. 14 in Basu et al. 2013) ...................................................................................................10 – Apex of paramere rather acute. Endosma: accessory sclerite and ventral sclerites not visible......................................................................................11 10 Metafemur with two long, divergent teeth on basal half (figs 11–12 in Basu et al. 2013)................................................................................V. mitrai – Metafemur with one long tooth on basal half (fig. 3 in Tran et al. 2009)..... .....................................................................................................V. tomokunii 11 Sub-apical part of paramere with distinct constriction (Fig. 4n). Endosma: lateral sclerites large, strongly sclerotized, dorsal sclerites distinctly sclerotized, medially with membranous parts (Fig. 4r, s) ..... V. motuoensis sp. nov. – Sub-apical part of paramere without distinct constriction. Endosma: lateral sclerites slender, dorsal sclerites weakly sclerotized (Fig. 4p, q, t, u) .........12 12 Body distinctly brighter, with large, bright yellow stripes along entire connexiva, median parts of mediotergites with distinct dark orange marks (Fig. 2k–l) ...................................................................V. yiliangensis sp. nov. – Body darker, with relative narrow orange stripes along connexiva, median parts of mediotergites without distinct dark orange marks (fig. 2d, f in Jin et al. 2023) ...................................................................................................13 13 Stripes along almost the entire connexiva except the posterior part of connexivum VII distinctly brighter (Fig. 2g, h). Prominent sub-apical tooth on the ventral side of the male metafemur significantly larger than the sub-basal one (Fig. 3a) ..............................................................V. lii sp. nov. – Stripes along the connexiva relatively dull or posteriorly reduced (fig. 2d, f in Jin et al. 2023). Prominent sub-apical tooth on the ventral side of the male metafemur not distinctly larger than the sub-basal one (fig. 5c, d in Jin et al. 2023 and figs 2, 4 in Tran et al. 2009) .........................................14 316 ZooKeys 1254: 313–329 (2025), DOI: 10.3897/zookeys.1254.156152 Siying Fu et al.: New species of subgenus Velia (Cesavelia) from China 14 Antennal segment I at least 1.6 times head width ......................V. sinensis – Antennal segment I around 1.4 times head width ....................... V. tonkina 15 Proctiger ovate, longer than broad (fig. 70 in Tran et al. 2009). Tergite VIII only with very short pubescence on hind margin. Connexiva swollen on segments III–IV; connexival spines long and caudally directed (figs 56– 57 in Tran et al. 2009) .............................................................. V. laticaudata – Proctiger about as long as broad or distinctly broader than long. Tergite VIII with more or less long hairs on hind margin. Connexiva not swollen; connexival spines short or dorso-caudally directed .................................16 16 Proctiger with more or less angulated sides (Fig. 4h, j, l; fig. 64–68 in Tran et al. 2009; fig. 17 in Basu et al. 2013 and fig. 7g–d in Jin et al. 2023) ...17 – Proctiger with rounded sides (fig. 71, 72 in Tran et al. 2009 and fig. 7e, f in Jin et al. 2023) .............................................................................................22 17 Proctiger much broader than long (Fig. 4j). Lateral parts of mediotergite I and laterotergites covered with dense silvery pubescence (Fig. 2c) ........... .................................................................................... V. motuoensis sp. nov. – Proctiger slightly broader than long. Lateral parts of mediotergite I and laterotergites covered with sparse silvery pubescence ............................18 18 Stripes along entire connexiva wide and bright yellow, median parts of mediotergites with distinct dark orange marks (Fig. 2e, f) ........................... .................................................................................... V. yiliangensis sp. nov. – Without such remarkable stripes along connexiva, median parts of mediotergites without distinct dark orange marks ...........................................19 19 Narrow stripes along almost the entire connexiva, except the posterior part of connexivum VII distinctly brighter (Fig. 2a, b) ..............V. lii sp. nov. – Narrow stripes along connexiva dull or posteriorly reduced (fig. 3e–h in Jin et al. 2023 and figs 4, 6 in Basu et al. 2013) ........................................20 20 Ventral part of abdomen bright orange (figs 4, 6, 10 in Basu et al. 2013) ... ............................................................................................................V. mitrai – Ventral part of abdomen dull or black (figs 3f, h, 4b, d, f, h, j, l in Jin et al. 2023) ............................................................................................................21 21 Antennal segment I at least 1.6 times head width ......................V. sinensis – Antennal segment I about 1.3 times head width.......................... V. tonkina 22 Proctiger with maximum width close to base, the basal part of lateral sides more convex than distal part (fig. 72 in Tran et al. 2009) ..............V. yunnana – Proctiger with maximum width approximately at mid-length ..................23 23 Proctiger with sides broadly rounded (fig. 7e, f in Jin et al. 2023). Connexival spines long (length of connexival spines distinctly greater than maximum width) and dorso-caudally directed (figs 58, 59 in Tran et al. 2009 and fig. 3a–d in Jin et al. 2023) ..................................................................24 – Proctiger with sides narrower (figs 65, 66 in Tran et al. 2009). Connexival spines short (length of connexival spines shorter than maximum width, or spines instinct) and caudally directed (figs 49–51 in Tran et al. 2009) ....... .....................................................................................................V. tomokunii 24 Connexiva nearly straight and almost parallel, connexival spines gradually sharpened in lateral view (Fig. 3a, b).....................................................V. bui – Connexiva convergent, connexival spines not gradually sharpened, sub-apical part slightly narrower than basal part in lateral view (fig. 3c, d in Jin et al. 2023 and figs 58, 59 in Tran et al. 2009) ...........V. longiconnexiva 317 ZooKeys 1254: 313–329 (2025), DOI: 10.3897/zookeys.1254.156152 Siying Fu et al.: New species of subgenus Velia (Cesavelia) from China Velia (Cesavelia) lii sp. nov. https://zoobank.org/3C57DBF6-F6E0-442F-90B7-26F1CA99E68E Figs 1a, b, 2a, b, g, h, 3a, 4a, b, g, h, m, p, q Material examined. Holotype: apterous ♂, China • Xizang Province, Linzhi City, Motuo County, Bangxin Village: 29.5763°N, 95.4643°E; 1360 m a.s.l.; 2024-VIII19; Zihe Li leg. (NKUM). Paratypes: 1 apterous ♀, same data as holotype (NKUM). Diagnosis. Body large (length 7.73–7.90, width 2.00–2.50), mainly brown. Connexiva of apterous female slightly curved in dorsal view, with bright yellow stripes along almost entire connexiva except posterior part of connexivum VII in both sexes (Figs 1a, b, 2a, b, g, h), connexival spines sharp and caudally directed in male, dorso-caudally directed in female (Fig. 2a, b, g, h); abdominal segment VIII of male stout and ventrally concave (Fig. 4a, b); proctiger of male broad, shield-shaped, posterior margin rounded (Fig. 4g); paramere broad, strongly curved, with thick setae on external side, apices sharp (Fig. 4m); endosoma of male stout, apical ends of lateral sclerites distinctly constricted, dorsal sclerites weakly sclerotized, translucent and curved, secondary ventral sclerite slender, accessory sclerite absent (Fig. 4p, q); proctiger of female broad, diamond-shaped (Fig. 4h). Comparative notes. Velia (Cesavelia) lii sp. nov. is most similar to V. bui in appearance. It can be distinguished from other species of Cesavelia by the following characters: the absence of the accessory sclerite in the male endosoma distinguishes this species from V. tomokunii J. Polhemus & D. Polhemus, 2003, V. championi Tamanini, 1955, and V. mitrai Basu, Subramanian & D. Polhemus, 2013 (Fig. 4p, q); the shape of the male proctiger (Fig. 4g) distinguishes this species from V. bui Jin, Fu & Ye, 2023, V. longiconnexiva Tran, Zettel & Buzzetti, 2009, V. anderseni Tran, Zettel & Buzzetti, 2009, V. laticaudata Tran, Zettel & Buzzetti, 2009, and V. yunnana Tran, Zettel & Buzzetti, 2009; and the bright yellow stripes along almost the entire connexiva except the posterior part of connexivum VII in both sexes (Figs 1a, b, 2a, b, g, h), and the prominent sub-apical tooth on the ventral side of the male metafemur, which is significantly larger than the sub-basal one (Fig. 3a), distinguish this species from V. sinensis and V. tonkina D. Polhemus & J. Polhemus, 2003. Due to the fact that V. steelei Tamanini, 1955 is only known from the macropterous female, and only the apterous female and male of V. lii sp. nov. have been collected to date, a comparison between the same forms is impossible (Tamanini 1995a). However, we note that V. steelei possesses long, erect setae on the extensor sides of the mesoand metatibia, these being longer than the tibial width (Tran et al. 2009). This characteristic is considered diagnostic (Tran et al. 2009) and is not found in V. lii sp. nov., thereby allowing for the distinction between these two species. Furthermore, the differences of the dorsal sclerites and lateral sclerites of the male endosoma distinguish V. lii sp. nov. from Velia (Cesavelia) motuoensis sp. nov. (Fig. 4p, q vs. Fig. 4r, s); and the larger body size and the differences of yellow stripes along the connexiva distinguish it from Velia (Cesavelia) yiliangensis sp. nov. (Fig. 2a, b, g, h vs. Fig. 2e, f, k, l). Description. Apterous male (holotype). Measurements. Body: length 7.73, width 2.00. Head: length 0.91, width: 1.16. Antenna: 5.75(1.98+1.26+1.23+1.28), length of antennal segment I about 1.71 times head width. Pronotum: width about 0.98 times its length (length 1.68, width 1.65). Lengths of leg segments 318 ZooKeys 1254: 313–329 (2025), DOI: 10.3897/zookeys.1254.156152 Siying Fu et al.: New species of subgenus Velia (Cesavelia) from China Figure 1. Habitus of females and males of Velia (Cesavelia) lii sp. nov. (a, b), Velia (Cesavelia) motuoensis sp. nov. (c, d) and Velia (Cesavelia) yiliangensis sp. nov. (e, f) in dorsal view. a, c, e apterous female b, d, f apterous male. (femur: tibia: tarsus (tarsal segment I + segment II + segment III)): fore leg: 2.47: 2.47: 0.96 (0.13+0.27+0.56); middle leg: 3.40: 3.90: 2.21 (0.10+1.20+0.91), length of mesotarsus II about 1.32 times length of mesotarsus III; hind leg: 3.40: 4.25: 2.07 (0.10+1.13+0.84), maximum width of metafemur: 0.42, length of metatarsus II about 1.35 times length of metatarsus III. 319 ZooKeys 1254: 313–329 (2025), DOI: 10.3897/zookeys.1254.156152 Siying Fu et al.: New species of subgenus Velia (Cesavelia) from China Color (Figs 1b, 2g, h). Body mainly dark brown, with scattered silvery pubescence. Pronotum with a row of black punctures near anterior margin and other punctures scattered on posterior lobe. Median part of anterior pronotal lobe and midline of pronotum dark orange. Sides of abdomen dark brown, with bright orange stripes along almost entire connexiva except posterior part of connexivum VII. Silvery pubescence usually distinctly denser on anterolateral corners of pronotum, lateral corners of metanotum, lateral parts of abdominal mediotergites II, V–VI, sparse on abdominal mediotergites I, III–IV and lateral parts of sternites. Structure. Body relatively large, covered with dense, short pubescence. Head (Figs 1b, 2g, h): triangular, almost perpendicular to thorax, without deflection; anteclypeus and postclypeus with dense, peg-like setae; antennal sockets prominent, antennal segment I much longer than head width, slightly thicker than antennal segments II–IV. Thorax (Figs 1b, 2g, h): width and length of pronotum approximately equal, posterior margin of pronotum broadly rounded, lateral parts of pronotum distinctly constricted at mid-length, median part slightly raised and lateral parts of anterior pronotal lobe concave; mesonotum completely hidden beneath pronotal lobe, with hind part of metanotum visible in dorsal view; lateral evaporatoriums slender, with a cluster of suberect, thick setae on each side; legs mainly with decumbent or suberect setae, tarsi of fore legs short, tarsi of middle and hind legs long and slender; profemora moderately incrassate, slightly curved and contracted subapically; mesofemora slender; metafemora (Fig. 3a) relatively slender, ventrally with two rows of small teeth and two prominent long teeth, the sub-apical tooth significantly larger and more prominent than the sub-basal one, metatibiae ventrally with two rows of small spines. Abdomen (Figs 1b, 2g, h): relatively slender; mediotergite I concave laterally, mediotergites II–VII almost flat; connexiva moderately raised, almost parallel, hardly converging, connexival spines short, sharp, caudally pointed; abdominal segment VIII (Fig. 4a, b) relatively stout, ventrally concave in lateral view, posteriorly with short, dense setae, posterodorsal margin of abdominal segment VIII medially emarginated. Genital segments (Fig. 4g, m, p, q): relatively large and visible in vitro; proctiger (Fig. 4g) shield-shaped, posterior margin rounded, with short, sparse setae; paramere (Fig. 4m) broad, strongly curved, with thick setae on external side, apices sharp; endosoma (Fig. 4p, q) stout, apical ends of lateral sclerites distinctly constricted, dorsal sclerites weakly sclerotized, translucent and curved, secondary ventral sclerite slender, accessory sclerite absent. Apterous female. Measurements. Body: length 7.90, width 2.50. Head: length 0.96, width: 1.24. Antenna I–III: (1.87+1.22+1.27), length of antennal segment I about 1.51 times head width. Pronotum: width about 0.94 times length (length 2.00, width 1.88). Lengths of leg segments (femur: tibia: tarsus (tarsal segment I + segment II + segment III)): fore leg: 2.70: 2.53: 0.98 (0.09+0.31+0.58); middle leg: 3.65: 4.00: 2.28 (0.11+1.24+0.93), length of mesotarsus II about 1.33 times length of mesotarsus III; hind leg: 3.65: 4.20: 2.21 (0.16+1.18+ 0.87), length of metatarsus II about 1.36 times length of metatarsus III. Color (Figs 1a, 2a, b). Similar to apterous male with following exceptions: silvery pubescence weaker on abdominal mediotergites III–VI (Fig. 2a). Structure. Body slightly larger than apterous male. Head (Figs 1a, 2a, b): Similar to apterous male. Thorax (Figs 1a, 2a, b): similar to apterous male with following exceptions: profemora slender; metafemora slender, ventrally with two rows of small spines, metatibiae ventrally without any 320 ZooKeys 1254: 313–329 (2025), DOI: 10.3897/zookeys.1254.156152 Siying Fu et al.: New species of subgenus Velia (Cesavelia) from China spines or teeth. Abdomen (Figs 1a, 2a, b): similar to apterous male with following exceptions: relatively stout; connexiva slightly convergent towards abdominal apex, connexival spines long, slender and straight, dorso-caudally directed. Genital segments: gonocoxae and gonapophyses semi-membranous, rami strongly sclerotized; proctiger (Fig. 4h) broad, diamond-shaped, posteriorly with short, sparse setae. Figure 2. Bodies of V. lii sp. nov. (a, b, g, h), V. motuoensis sp. nov. (c, d, i, j) and V. yiliangensis sp. nov. (e, f, k, l). a–f. Apterous female; g–l. Apterous male. 321 ZooKeys 1254: 313–329 (2025), DOI: 10.3897/zookeys.1254.156152 Siying Fu et al.: New species of subgenus Velia (Cesavelia) from China Macropterous female and macropterous male. Unknown. Etymology. The species is named in honor of Dr Zihe Li, who is the only one to successfully collect the specimens from a hazardous mountain stream. Habitats. This species inhabits areas near rocks or the banks of fast-flowing mountain streams (Fig. 5a). Distribution. China (Xizang) (Fig. 6). Velia (Cesavelia) motuoensis sp. nov. https://zoobank.org/7E0F62B1-16AD-459B-8A0C-C5EC0AF50E46 Figs 1c, d, 2c, d, i, j, 3b, 4c, d, i, j, n, r, s Material examined. Holotype: apterous ♂, China • Xizang Province, Linzhi City, Motuo County, Motuo Village: 29.3051°N, 95.3567°E; 1936 m a.s.l.; 2024-VIII20; Zezhong Jin, Zihe Li leg. (NKUM). Paratypes: 1 apterous ♂, 3 apterous ♀, same data as holotype (NKUM). Diagnosis. Body large (length 6.90–7.10, width 2.00–2.25), mainly brown. Connexiva of apterous female slightly curved, convergent posteriorly in dorsal view, with orange stripes along connexiva in both sexes (Figs 1c, d, 2c, d, i, j), connexival spines sharp and caudally directed in males, dorso-caudally directed in females (Fig. 2c, d, i, j); abdominal segment VIII of male stout and ventrally concave (Fig. 4c, d); proctiger of male broad, shield-shaped, posterior margin rounded (Fig. 4i); paramere broad, strongly curved, with thick setae on external side, apices sharp (Fig. 4n); endosoma of male stout, lateral sclerites large, strongly sclerotized, apical ends of lateral sclerites distinctly constricted, dorsal sclerites distinctly sclerotized, translucent and curved, with membranous parts medially, secondary ventral sclerite stout, accessory sclerite absent (Fig. 4r, s); proctiger of female broad, diamond-shaped, lateral dilations distinct (Fig. 4j). Comparative notes. Velia (Cesavelia) motuoensis sp. nov. is most similar to V. longiconnexiva in appearance. It can be distinguished from other species of Cesavelia by the following characters: the absence of the accessory sclerite in the male endosoma distinguishes this species from V. tomokunii, V. championi, and V. mitrai (Fig. 4r, s); the shape of the male proctiger (Fig. 4i) distinguishes this species from V. bui, V. longiconnexiva, V. anderseni, V. laticaudata, and V. yunnana; and the characteristics of the endosomal sclerites, especially the large lateral sclerites and dorsal sclerites with membranous parts medially, distinguish this species from V. sinensis, V. tonkina, V. lii sp. nov. and V. yiliangensis sp. nov. (Fig. 4r, s vs. Fig. 4p, q, t, u). The extensor sides of the mesoand metatibia without long, erect setae and the shape of the female proctiger (Fig. 4j) distinguish this species from V. steelei. Description. Apterous male (holotype). Measurements. Body: length 6.90 (6.90–7.10), width 2.00 (2.00–2.13). Head: length 0.70, width: 1.15. Antenna: 5.43 (1.89+1.27+1.20+1.07), length of antennal segment I about 1.64 times head width. Pronotum: width about 1.12 times its length (length 1.50, width 1.68). Lengths of leg segments (femur: tibia: tarsus (tarsal segment I + segment II segment III)): fore leg: 2.50: 2.27: (0.09+0.24+(segment III missing)); middle leg: 3.30: 3.50: 2.13 (0.13+1.16+ 0.84), length of mesotarsus II about 1.38 times length of mesotarsus III; hind leg: 3.25: 3.55: 1.99 (0.12+1.07+ 0.80), maximum width of metafemur: 0.51, length of metatarsus II about 1.34 times length of metatarsus III. 328 ZooKeys 1254: 313–329 (2025), DOI: 10.3897/zookeys.1254.156152 Siying Fu et al.: New species of subgenus Velia (Cesavelia) from China also demonstrate distinct patterns in their distribution. Velia tomokunii, V. championi, and V. mitrai are found in the western regions of the southern slopes of the Himalayas (Fig. 6), whereas V. bui, V. longiconnexiva, V. laticaudata, and V. yunnana are distributed across the Hengduan Mountains and central China, generally to the east of the Cesavelia distribution area (Fig. 6). The remaining species are continuously distributed within this geographical range. Color patterns and the shape of the connexival spines exhibit considerable intraspecific diversity (Tran et al. 2009; Jin et al. 2023), and do not appear to be reliable indicators for assessing phylogenetic relationships. We have observed a high species diversity of Cesavelia in the Himalayan and Hengduan Mountain regions. The reconstruction of the phylogenetic relationships within this subgenus, along with an in-depth investigation into how the Himalayas and Hengduan Mountains have influenced its speciation, dispersal, and diversification, warrants further study. Species list of Velia (Cesavelia) recorded in China V. sinensis Sichuan Province V. tonkina Yunnan Province V. yunnana Yunnan Province V. longiconnexiva Guizhou Province V. bui Hubei Province V. lii sp. nov. Xizang Province V. motuoensis sp. nov. Xizang Province V. yiliangensis sp. nov. Yunnan Province Acknowledgements We express gratitude to Mu Qiao for collecting specimens of V. yiliangensis sp. nov., and Zihe Li for collecting specimens of V. motuoensis sp. nov. and V. lii sp. nov. for this research. Moreover, we would also express our appreciation to the Xizang Autonomous Region Forestry and Grassland Bureau, Linzhi Forestry and Grassland Bureau, for providing permissions and assistance for our fieldwork in Xizang Province. Additional information Conflict of interest The authors have declared that no competing interests exist. Ethical statement No ethical statement was reported. Use of AI No use of AI was reported. Funding This study was supported by the Natural Science Foundation of China (No. 32470467, No. 32400359), the National Science Foundation of Tianjin, China (No. 24JCYBJC01910), and the Fundamental Research Funds for the Central Universities (No. 63253184). 329 ZooKeys 1254: 313–329 (2025), DOI: 10.3897/zookeys.1254.156152 Siying Fu et al.: New species of subgenus Velia (Cesavelia) from China Author contributions All authors have contributed equally. Author ORCIDs Siying Fu https://orcid.org/0000-0001-7010-4401 Zezhong Jin https://orcid.org/0000-0001-7223-770X Zhen Ye https://orcid.org/0000-0003-2327-1869 Data availability All of the data that support the findings of this study are available in the main text. References Andersen NM (1981) A new genus of Veliinae and descriptions of new Oriental species of the subfamily (Hemiptera: Veliidae). 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