Nasoonaria pseudoembolica, Tanasevitch, 2019

Tanasevitch, Andrei V., 2019, A new genus and two new species of linyphiid spiders (Arachnida: Araneae) from Vietnam, Raffles Bulletin of Zoology 67, pp. 129-134 : 134

Nasoonaria pseudoembolica , new species

( Figs. 4–6 , 14–20 )

Holotype male ( ZMMU), VIETNAM, Dong Nai Province, Ma Da forest [= rung Ma Da ], from soil sample, 20 May1995, coll. T.K. Sergeeva .

Paratype: 1 female ( ZMMU), collected together with the holotype.

Etymology. The specific epithet is a Latin adjective referring to the presence of an embolic-like process [= radical apophysis] in the embolic division.

Diagnosis. The new species is diagnosed by the presence of an embolus-like radical apophysis in the embolic division and by the characteristic shape of the epigynal cavity.

Description. Male holotype. Total length 2.03. Carapace 0.90 long, 0.75 wide, unmodified, as shown in Fig. 4 , yellow to pale brown. Chelicerae 0.35 long, a mastidion absent. Legs yellow. Leg I 3.51 long (0.93+0.28+0.95+0.75+0.60); IV 3.41 long (0.90+0.28+0.88+0.85+0.50). Chaetotaxy: 2.2.1.1. Length of spines 1.5–2.5 diameters of leg segment. All metatarsi with a trichobothrium. TmI 0.64. Palp ( Figs. 14–17 ): tibia wide, elongated, with a retrolateral obtuse outgrowth. Prolateral edge of tibia undulate. Paracymbium L-shaped, with a long and narrow distal part, uncinate apically. Distal suprategular apophysis hypertrophied, falcate. Median membrane relatively narrow and long, tongue-shaped. Embolic division with a small and partly membraneous radix. Embolus thin, long, whip-shaped; a dark, falcate, embolus-like, radical apophysis starting at base of embolus. Abdomen 1.13 long, 0.65 wide, dorsal pattern as in Fig. 4 .

Female. Total length 2.00. Carapace 0.75 long, 0.68 wide, unmodified, as shown in Fig. 5 . Chelicerae 0.33 long, a mastidion absent.Leg I 2.93 long (0.80+0.25+0.75+0.63+0.50); IV 3.11 long (0.88+0.23+0.75+0.75+0.50). All metatarsi with a trichobothrium. TmI 0.64. Abdomen 1.25 long, 0.83 wide, dorsal pattern as in Fig. 5 . Epigyne ( Figs. 6 , 18–20 ): epigynal cavity shallow, trapeziform, its lateral walls slightly concave, anterior part of cavity with a prominence. Posterior median plate [= dorsal plate] short and wide, with a hollow at posterior edge. Receptacles bean-shaped. Body ( Figs. 5, 6 ) and leg colouration, as well as chaetotaxy as in male.

Taxonomic remarks. The species is similar to Nasoonaria sinensis Wunderlich & Song, 1995 , but can be distinguished by the simple male palpal tibia (vs. strongly modified in N. sinensis ), the presence of an embolus-like process in the embolic division, and by the presence of an epigynal cavity in the female (vs. absent in N. sinensis ).

Distribution. So far known only from the type locality in southern Vietnam.

Figures

Figs. 1–6. Habitus of Vietnagone silvatica, new species (1–3) and Nasoonaria pseudoembolica, new species (4–6). 1, 4, male holotype; 2, 3, 5, 6, female paratype; 1, 2, 4, 5, dorsal view; 3, 6, ventral view.

Figs. 14–20. Details of palpal and epigynal structure of Nasoonaria pseudoembolica, new species. 14–17, male holotype; 18–20, female paratype. 14, 15, right palp, retrolateral and prolateral views, respectively; 16, palpal tibia, dorsal view; 17, embolic division; 18, 19, epigyne, ventral views, different aspects; 20, epigyne, dorsal view.