A description of a new species of the genus Promesomachilis from Spain (Insecta : Microcoryphia)

A description of a new species of the genus Promesomachilis from Spain (Insecta: Microcoryphia) Carmen Bach de Roca Unitat de Zoologia, Departament de Biologia Animal, de Biologia Vegetal i d’Ecologia, Universitat Autònoma de Barcelona. E-08193 Bellaterra, Barcelona, Spain e-mail: [email protected] Pietro Paolo Fanciulli Dipartamento di Biologia Evolutiva, Università di Siena, Italy Miguel Gaju-Ricart Rafael Molero-Baltanás Departamento de Zoología, Universidad de Córdoba, Spain Manuscript received in September 2007 Abstract A new Microcoryphian species is described from southern Spain. The new species belongs to the genus Promesomachilis and is named P. intermedia n. sp. because of the presence of intermediate characteristics in comparison with the other two species of the genus. The main features of the new species are: male maxillary palp with a field of spiralized setae on the ventral side of articles II-V, some setae also on article VI; second article of the male labial palp without a process on its distal part, though a little protuberant; labial palp also lacks a field of specialized setae, which are present in the two other species; each female gonapophysis with only 14-16 annuli, the lowest number ever found in the genus. The main feature that allow us to distinguish the three species is the presence of a sensorial field on femur II and III. In P. intermedia it is on the outer part of the femur, whereas in the other two species it is different. Key words: Insecta, Microcoryphia, new species, Promesomachilis, Spain Resumen. Descripción de una nueva especie de Promesomachilis de España (Insecta: Microcoryphia) Se describe una nueva especie de Microcoryphia procedente del sur de España a la que denominamos Promesomachilis intermedia n. sp., por presentar caracteres intermedios entre las dos únicas que se conocían del género. La nueva especie puede caracterizarse por las siguientes particularidades: la parte ventral de los artejos II a V del palpo maxilar posee un campo de sedas espiraladas que también se encuentran, aunque en menor número, en el artejo VI; la parte dorsal del segundo artejo del palpo labial del macho no presenta ni la protuberancia (apenas perceptible en la nueva especie), ni el campo de sedas espeOrsis 22, 2007 45-56 ciales que se hallan en las otras dos; las gonapófisis de la hembra constan de 14-16 divisiones, el menor número entre las tres especies. La principal característica que permite separar la nueva especie de las otras dos es la presencia, en los dos sexos, de un campo sensorial en la cara externa del fémur del segundo y tercer par de patas. En las otras especies, este campo está situado en otros pares de patas. Palabras clave: Insecta, Microcoryphia, nueva especie, Promesomachilis, España. Introduction The genus Promesomachilis Silvestri, 1923 is endemic from the Iberian Peninsula and northwestern Morocco. Two species are known from the Iberian Peninsula: P. hispanica Silvestri, 1923 and P. cazorlensis Bach, 1983. An allozyme electrophoresis analysis comparing three populations from southern Spain (Fanciulli et al., 1995), revealed the presence of remarkable genetic differentiation of the population collected in Alhaurín de la Torre (Málaga). Morphological investigations on other specimens from Alhaurín de la Torre also revealed some important differences that induced us to describe a new species: P. intermedia n. sp. Material and methods The specimens were dissected and mounted in slides following the standard procedure. A recent description of this method could be seen in Molero et al. (2004). Micrographs were obtained by means of scanning electron microscopy. Material preserved in ethanol 80% was dehydrated in absolute ethanol, critical-pointdried in a Balzer CPD 030 apparatus, and coated with gold in a Balzers MED 010 sputter coater. Observations were performed with a Philips XL20 scanning electron microscope. Systematics We describe a new species of Microcoryphia: Promesomachilis intermedia n. sp. Description of the male Body length: 9 mm; Length of the antennae (broken): 4 mm; length of paracercus: 9mm; length of cerci: 4 mm. Body and appendages are slightly pigmented. The head has pigmentation only around the median ocellus: the front, that protudes between the ocelli, has a tiny pigmentation. Ratio contact line/length of the eyes: 0.55, length/width of the eyes: 0.90 (Fig. 1A). The antennae are longer than the body (as we have observed in another specimen), scapus ratio maximum length/maximum width: 1.5-1.6; the distal chain 46 Orsis 22, 2007 C. Bach de Roca; P. Paolo Fanciulli; M. Gaju-Ricart; R. Molero-Baltanás A new species of Promesomachilis from Spain Orsis 22, 2007 47 Figure 1. Promesomachilis intermedia n. sp. male. A: Head in lateral view. B: Outline of the labial palp. C: Sensory cones of the apex of third article of the labial palp. D: Maxillary palp in external view. E: Setae of the ventral field of the maxillary palp. Scales: 0.1 mm. A DE BC with 14 annuli, each one show two rows of bristles with sensilla showing irregular distribution. The flagellum has alternatively white and brown segments (Figs. 2 A,B). The maxillary palp shows very little brown pigment; it has normal setae and a field of spiralized setae on the ventral side of articles II-V and some others on article VI. The distribution of the hyaline striated spines on the last three articles is: 5:3; 6:15; 7:12 (Figs. 1D, E, 2E). Ratio n/(n-1): 0.69. The apical part of the third article of the labial palp is widened (typical of the genus) and covered with normal bristles, sensory cones and small sensorial setae (Figs. 1B, C, 2C, D). The second article, a little protruded in the distal part, lacks special bristles or setae, as it occurs in the other two species. The three pairs of legs show tiny macrochaetae on the coxa. The femur of the foreleg is broader than in the other legs. Midleg without coxal stylet; the femur has a row of sensilla in the outer ventral side. Hindleg with coxal stylet; femur with a field of sensilla on the outer ventral side. The femur also has ciliary bristles on his ventral side. In addition of the normal setae, all legs show spiniform setae on the trochanter, femur, tibia and tarsomeres that, sometimes, appear as spines. (Figs. 2F, 3A-C). Urosternites II-V with acutangle sternite (Fig. 4A); VI-VII with rectangular one; coxites II-V with two pairs of eversible vesicles; urosternite VIII without parameres; urosternite IX bear the penis and parameres (Fig. 3D). Ratio coxite/stylet (without spine): II-VII: 1.5 -1.86; VIII: 1.21; IX:1.17; ratio spine/stylet (without spine): II-VII: 0.30 – 0.38; VIII: 1.21; IX: 0.19. Paramera IX with 1+6-7 divisions covered with small spines on his inner side (Figs. 3D, 4B). Penis a little longer than the paramera, showing a circular opening with bristles around the circle a papillae inside (Figs. 3D, 4C). Ratio basal part/distal part: 1.12. Cerci ending with two spines having different lengths (Fig. 3E). Description of the female: Body length: 10 mm; length of the antennae (broken): 4.5 mm; length of paracercus: 9 mm; length of cerci: 3.5 mm. The head shows similar features as the male. Eyes ratio contact line/length of eyes: 0.52; length/width: 1.0. Length and sensilla of the antennae as in the male. The maxillary palp shows diffuse and uniform pigment. It lacks the field of spiralized setae. The outline is as on Fig. 5 A. The distribution of the hyaline spines on the last three articles is: 5:3; 6:16-20; 7:15-16. Ratio n/(n-1): 0.72. The last article of the labial palp is slightly widened. Shape of sensory cones as in the male (Fig. 5B). All legs with macrochaeta on the dorsal side of the femur. Forelegs with a slightly widened femur. Midleg and hindleg have a sensory field as in the male. The three pair of legs bear spiniform setae on the ventral side of the femur, tibiae and tarsi (Figs. 5C-E, 6A-C). 48 Orsis 22, 2007 C. Bach de Roca; P. Paolo Fanciulli; M. Gaju-Ricart; R. Molero-Baltanás A new species of Promesomachilis from Spain Orsis 22, 2007 49 A B C D E F Figure 2. Promesomachilis intermedia n. sp male. A: Annuli of the antennal chain. Scale: 100 μm. B: Row of setae and sensilla of the annuli. Scale: 50 μm. C: Third article of the labial palp. Scale: 200 μm. D: Sensory cones of the third article of the labial palp. Scale: 20 μm. E: Shape of the spines on the dorsal side of the 5th, 6th and 7th articles of the maxillary palp. Scale: 60 μm. F: Femur of the 2nd pair of legs showing the field of sensory sensilla. Scale: 200 μm. 50 Orsis 22, 2007 C. Bach de Roca; P. Paolo Fanciulli; M. Gaju-Ricart; R. Molero-Baltanás Figure 3. Promesomachilis intermedia n. sp. male. A. First pair of legs. B: Second pair of legs showing the sensorial field of sensilla on the femur. C: Id. third pair of legs. D: IX urosternite with penis and paramera. E: End of the cerci. Scales: 0.1 mm. A B C DE A new species of Promesomachilis from Spain Orsis 22, 2007 51 B A C Figure 4. Promesomachilis intermedia n. sp male. A: Coxite of the V urosternite. Scale: 100 μm. B: Spines on the ventral side of paramera. Scale: 50 μm. C: Papilla inside the penis opening. Scale: 20 μm. 52 Orsis 22, 2007 C. Bach de Roca; P. Paolo Fanciulli; M. Gaju-Ricart; R. Molero-Baltanás Figure 5. Promesomachilis intermedia n. sp. female. A: Outline of the maxillary palp. B: Id. labial palp. C: Id. first pair of legs. D: Id. second pair of legs showing the sensorial field of sensilla. E: Id. Third pair of legs. F: VII urosternite. Scales: 0.1 mm. A B C D E F Urosternites as in the male. Sternites showing rectangular shape. Coxite VII is ventrally prolonged between the stylets (Fig. 5F). Ratio length of the stylet (without spine)/length of coxite: V-VII: 0.45-0.52; VIII: 0.71; IX: 0.61. Ratio length of spine/length of stylet (without spine): II-VII: 0.33; VIII: 0.29; IX: 0.23. The ovipositor is of the primary type (Sturm and Bach de Roca, 1992) and is a little longer than the apex of the IX coxites. Gonapophysis VIII with 1+14-16 divisions all of them with long ciliary bristles as long as or longer than the width of the division. Last division with 4-5 conules, the other divisions, from the apex, have respectively 1-2, 1 and 1 conules (Figs. 6D-E, 7A). Gonapophysis IX with 1+14-16 divisions all of them covered with ciliary bristles as long or a little longer than the width of the division. The gonapophysis end with a strong tooth. There are some spines on the ventral side (Figs. 6F, 7B). The number of conules from the apex are: 4-5, 1-2, 1, 1, and 1. End of the cerci as in the male. Derivation of the name: The new species is named Promesomachilis intermedia, because it shows intermediate features in comparison to the other two species of the genus. Type material: Alhaurin de la Torre (Málaga) 1 male holotype + 6 males + 6 females paratypes. Reference: M 507 (2 males + 2 females do not exist because have been used in scanning electron microscopy), 29-03-93, Road C-344, Km 79 Arroyo Hondo; Alhaurin de la Torre (Ma), 2 males paratypes, 14-02-93. Reference: M 888 Discussion The genus Promesomachilis gives its name to a group of Microcoryphia genera also including Bachilis, Catamachilis and Pseudocatamachilis (Sturm & Bach de Roca, 1993). All of them are endemic in the Iberian Peninsula except Promesomachilis that was also found in the North Africa. The presence of a sensorial field on the legs, observed for the first time in the new species, led us to review also P. hispanica and the types of P. cazorlensis, the other two species of the genus. This sensory field is also present in these species, both in the males and in the females but it appears located in different legs in each species (though it always exist on the P. II). On the basis of this character we can distinguish the three species one from another (Table 1). In addition to this important character, the males also show other important morphological differences on the maxillary and labial palps (see Table 1). The following key can be used to distinguish the three species: 1.- Sensorial field present only on the external-ventral side of the femur of the second pair of legs .............................. Promesomachilis hispanica Silvestri, 1923 A new species of Promesomachilis from Spain Orsis 22, 2007 53