Callitrichia asela, Tanasevitch, 2023

Tanasevitch, Andrei V., 2023, Survey of the Ethiopian linyphiid spider fauna. I. Subfamily Erigoninae (Arachnida, Araneae, Linyphiidae), Zootaxa 5346 (4), pp. 420-442 : 422-424

Callitrichia asela new species

Figs 1 , 2

Type material. Holotype: J ( ZMMU): ETHIOPIA, Chilalo Mt., canyon, SE slope, 3125–3130 m a.s.l., 7.93414°N 39.19479°E, Hypericum revolutum bushes with sporadic Schefflera abyssinica and Hagenia abyssinica , grass, green mosses, sifting litter and mosses, 29.X.2022, A. Tanasevitch leg. [Eth017 ]. Paratypes: 5J, 6♀ ( ZMMU): same date and locality, together with holotype; 5J, 6♀ ( ZMMU): Chilalo Mt., canyon, steep northern slope, 3080 m a.s.l., 7.93524°N 39.19368°E, Hypericum revolutum bushes with sporadic Schefflera abyssinica , grass, green mosses, sifting litter and mosses, 24.X.2022, A. Tanasevitch leg. [Eth014]; 2J, 5♀ ( MHNG): Chilalo Mt., canyon, steep northern slope, 3070–3075 m a.s.l., 7.935124°N 39.19392°E, Hypericum revolutum bushes with sporadic Schefflera abyssinica , grass, green mosses, sifting litter and mosses, 24 & 29.X.2022, A. Tanasevitch leg. [Eth016]; 2J, 5♀ ( ZMMU): Oromia Region, Asela Zone, ca 35air-km SE from Asela (= Assela), Arsi Mountains N.P., road from Digelu to Ticho, top of mountains, 3755–3770 m a.s.l., 7.82377°N 39.41713°E, Erica arborea bushes, Alchemilla sp. , green mosses mostly Rhytidiadelphus triquetrus , sifting mosses from beds of Erica , 21 & 31.X.2022, A. Tanasevitch leg. [Eth019]; 8♀ ( ZMMU):Arsi Mountains N.P., road from Digelu to Ticho, 3500–3505 m a.s.l., 7.81944°N 39.35429°E, Erica arborea bushes, with grass and green mosses, sifting mosses, 30 & 31.X.2022, A. Tanasevitch leg. [Eth018].

Etymology. The specific epithet is a noun in apposition referring to the Asela Zone in Oromia Region, Ethiopia, the area of origin of the new species.

Diagnosis. By the shape of the palpal tibia and the structure of the embolic division, the new species seems to be especially similar to both C. ruwenzoriensis Holm, 1962 , from Uganda, and C. glabriceps Holm, 1962 , from both Kenya and Uganda ( Holm 1962). The male of C. asela n. sp. clearly differs from both above congeners by the shape of the carapace, the shapes of the apical projections of the palpal tibia and the presence of a distinct notch between them (marked with an arrow in Fig. 2D ). From C. ruwenzoriensis , the new species differs also in the low distal apophysis of the convector being smaller, and from C. glabriceps by the wider embolus. The female is distinguished from C. ruwenzoriensis by the narrower epigynal plate, and from C. glabriceps by the rounded shape of the epigynal plate (vs subrectangular).

Description. Male (Paratype from Eth017). Total length 2.35. Carapace modified, as in Figs 1A–D, 1.10 long, 0.75 wide, greyish to greyish-yellow, with dark radial stripes. Head part of carapace with a rounded elevation holding the posterior median eyes; face of carapace with a group of bristles of different length. Eyes normal, not enlarged. Chelicerae 0.40 long, a mastidion absent. Legs greyish to greyish pale yellow. Leg I 2.91 long (0.85 + 0.28 + 0.65 + 0.63 + 0.50), IV 3.36 long (0.88 + 0.30 + 0.83 + 0.85 + 0.50). Chaetotaxy 2.2.1.1, spines about as long as 1–2 diameter of corresponding leg segment. Metatarsi I–IV with a trichobothrium each. TmI 0.60. Palp ( Figs 2A–F ): Tibia short, apically with a notch divided tibial distal part into two short parts: a prolateral part with a small apical claw, and retrolateral part with two apical claws. In addition, a small denticle situated at frontal surface of tibia (marked with an arrow in Figs. 2E and 2C ). Paracymbium large, thick, unciform. Tegulum somewhat elongated, distally membraneous, slightly bent apically. Distal suprategular apophysis short, wide, with a small and narrow tooth at middle. Median membrane small, poorly visible. Embolus short, claw-shaped. Convector massive, its upper distal apophysis small, claw-shaped; low distal apophysis as a small tubercle. Opistosoma 1.20 long, 0.80 wide, dorsal pattern as in Fig. 1A .

Female (Paratype from Eth017). Total length 2.65. Carapace unmodified, as in Figs 1E, F , greyish to greyish-yellow, with dark radial stripes, 1.03 long, 0.75 wide. Chelicerae 0.43 long. Legs greyish to greyish-pale brown. Leg I 2.76 long (0.75 + 0.30 + 0.63 + 0.60 + 0.48), IV 3.15 long (0.82 + 0.30 + 0.78 + 0.80 + 0.45). Chaetotaxy and thrichobothriotaxy as in male TmI 0.59. Opisthosoma 1.75 long, 1.10 wide, dorsal pattern as in Fig. 1E . Epigynum ( Figs 1G , 2H, I ): Epigynal plate oval, receptacles elongated, bean-shaped, directed forward and slightly apart.

Distribution. Known only from the mountains of Oromia Region, Ethiopia, ranging from 3070 to 3770 m a.s.l.

Figures

FIGURE 1. Photographs of male (A, B, C, D) and female (E, F, G) of Callitrichia asela n. sp., paratypes from Eth017. A, E, habitus, dorsal view; B, same, lateral view; C, prosoma, antero-lateral view; D, F, habitus frontal view; G, opisthosoma, ventral view. Scale bars: 0.5mm.

FIGURE 2. Details of male palpal structure (A–G) and female epigynum (H, I) of Callitrichia asela n. sp., paratypes from Eth017. A, B, right palp, retrolateral and prolateral view, respectively; C, tibia and paracymbium, postero-prolateral view; D, tibia, dorsal view; E, same, frontal view; F, G, distal suprategular apophysis and embolic division, prolateral and retrolateral view, respectively; H, I, cleared epigynum, ventral and dorsal view, respectively. Scale bars: 0.1mm.