Tapinocyba formosa, Tanasevitch, Andrei V., 2011

Tanasevitch, Andrei V., 2011, On some linyphiid spiders from Taiwan (Araneae: Linyphiidae), Zootaxa 3114, pp. 31-39 : 38-39

Tapinocyba formosa new species

Figs 11–14 , 22–28

Type material: Holotype: 3, Taiwan (R.O.C.): Yilan County, Da Tong Township, Ming Ch’ih (= Mingchih), km 66.5 of Road 7, 1000 m a.s.l., fern litter and rotting wood, 22.II.2010, leg. S. Vit [TAIW-10/5]. Paratypes: 13, 4Ƥ, same locality and date, together with holotype.

Etymology. The species name refers to the old name of the island; adjective.

Diagnosis. The new species can easily be distinguished from the known Asian congeners (see below) by the shape of both palpal tibia and embolic division in the male, as well as by the anchor-shaped ventral plate of the epigynum in the female.

Description. Male (paratype): Total length 1.85. Carapace 0.93 long, 0.75 wide, pale brown, modified with raised cephalic part and lateral pit behind posterior lateral eyes, as shown in Figs 11, 12 . Chelicerae 0.25 long, unmodified. Legs pale brown. Leg I, 2.03 long (0.60+0.20+0.53+0.40+0.33), IV, 2.03 long (0.60+0.20+0.53+0.40+0.30). Chaetotaxy 1.1.1.1, spines weak, their length being 0.5–1 diameter of segment. TmI, 0.39. Metatarsi IV without trichobothrium. Palp ( Figs 22–28 ): Patella with a small pointed tubercle apically. Paracymbium rather small and narrow, L-shaped. Tegulum with a membranous protegulum. Distal suprategular apophysis poorly expressed. Embolic division small and simple. Embolus as a short, slightly curved, thin spine. Opisthosoma 1.00 long, 0.70 wide, grey.

Female: Total length 1.75. Carapace 0.78 long, 0.63 wide. Chelicerae 0.33 long, unmodified. Leg I, 1.97 long (0.58+0.23+0.45+0.38+0.33), IV, 1.99 long (0.58+0.20+0.53+0.38+0.30). Chaetotaxy 1.1.1.1, spines weak, as long as or a little longer than diameter of segment. TmI, 0.40. Opisthosoma 1.05 long, 0.70 wide. Epigynum: Ventral plate anchor-shaped, receptacles subspherical ( Fig. 13 ). Vulvae as shown in Fig. 14 . Body and leg coloration, as well as chaetotaxy as in male.

Taxonomic remarks. The somatic characters (the modified carapace, the chaetotaxy, etc) and the structure of the genitalia (the poorly expressed DSA, the simple embolic division with the short embolus and the unmodified radix, as well as the general appearance of the epigynum), clearly supports the generic inclusion of the new species in Tapinocyba Simon, 1884 . There are only three Tapinocyba species currently known from the Far-eastern part of the Asia: the East Palaearctic T. kolymensis Eskov, 1989 ( Song et al. 1999) , and the Japanese T. silvicultrix Saito, 1980 and T. suganamii Saito & Ono, 2001 ( Saito 1980, Saito & Ono 2001). From these congeners T. formosa n. sp. clearly differs by the presence of the head elevation on carapace, shape of the palpal tibia, and the spine-shaped embolus in male, as well as by the anchor-shaped ventral plate of the epigynum.

Distribution. Known from the type locality only (see Fig. 29 ).

Figures

FIGURE 29. Collecting localities in Taiwan. Cross –– Gongylidioides diellipticus Song & Li, 2008; Square –– Maculoncus orientalis n. sp.; triangle –– Micrargus herbigradus (Blackwall, 1854) & Oia imadatei (Oi, 1964); circle –– Oreonetides taiwanus n. sp. and Tapinocyba formosa n. sp.; s tar –– Solenysa longqiensis Li & Song, 1992.

FIGURES 7 – 14. Micrargus herbigradus (Blackwall, 1854) (7, 8), Oreonetides taiwanus n. sp. (paratype) (9, 10) and Tapinocyba formosa n. sp. (paratype) (11 – 14). 7, 8 –– right palp (retrolateral and prolateral, respectively); 9 –– embolus; 10 –– suprategulum and distal suprategular apophysis; 11, 12 –– male carapace (lateral and dorsal, respectively); 13 –– epigynum (ventral view); 14 –– vulva (dorsal). Abbreviations used: D –– sperm duct; EP –– embolus proper; MM –– median membrane; PH –pit hook; SS –– serrate surface; Th –– thumb. Not to scale.

FIGURES 22 – 28. Details of palp structure in Tapinocyba formosa n. sp. (paratype). 22, 23 –– right palp (retrolateral and prolateral, respectively); 24 –– palpal tibia and paracymbium (lateral); 25, 26 –– palpal tibia (dorsal, different aspects); 27 –suprategulum and embolic division; 28 –– embolic division. Abbreviations used: ARP –– anterior radical process; E –embolus. Scale bar: 0.1 mm.