Orchestina bialata, Liu, Keke, Xiao, Yonghong & Xu, Xiang, 2016

Liu, Keke, Xiao, Yonghong & Xu, Xiang, 2016, On three new Orchestina species (Araneae: Oonopidae) described from China, Zootaxa 4121 (4), pp. 431-446 : 435-439

Orchestina bialata sp. nov.

Figures 5−7 , 11 .

Type material. Holotype female: China, Jiangxi Province: Ji’an City, Jinggangshan Country Level City, Ciping Town, Dajing village, Peak of Leaders, forest, 26.5700°N, 114.1209°E, 945m, 8.XII.2013, Zhiwu Chen, Keke Liu and Benqiang Xiao leg. (OON 7). Paratypes: 1 female, same data as holotype (OON 8); 7 females, same data as holotype, Huangyangjie, bamboo forest, 26.456°N, 114.106°E, 958m, 5.IV.2014, Zhiwu Chen, Keke Liu, Xiaoping Huang, Zeyuan Meng, and Yubao Tang leg. (OON 9−15).

Etymology. The specific name is a Latin adjective, meaning “bialate” and referring to the two long lateral protrusions (Pr).

Diagnosis. Females of the new species can be easily recognized by the genitalia with ventral triangular sclerotized plate, the peculiar AUS ( Figs 5G , 6D −E , 7D ) with long recurved Pr and basally with the lateral extensions (Ex2) of the posterior plate strongly procurved.

Description. Female. Habitus as in Figs 5A, B . Total length 1.32, carapace ( Fig. 5C ) yellow, length 0.61, width 0.46, strongly elongate oval in dorsal view (CW/CL ≈ 0.76), pars cephalica slightly elevated in lateral view, anteriorly and posteriorly narrowed to around 0.6 times its maximum width, smooth surface, with two groups of four setae on laterally rounded corners near ALE. Eyes ( Figs 5C, D ): PME roughly circular, touching; diameters: ALE 0.05, PME 0.08, PLE 0.06, PME 1.3 times PLE; ALE −PME touching, PLE −PME separated from less than PME radius. Clypeus ( Figs 5D , 6A ) margin unmodified, anteriorly curved downwards in frontal view, sloping forward in dorsal view. Sternum ( Fig. 5E ) as long as wide, anterior margin unmodified, shield-shaped, yellowish white, surface smooth. Mouthparts ( Figs 5D, E , 6A, B , 7A, B ): Chelicerae straight, each with row of 3 setae on the distal part ( Figs 6A , 7A ); labium ( Figs 6B , 7B ) subcircular with constricted base, with 4−6 median setae on anterior margin, unique setae near base and two rows of 3 setae in center and posterior part ( Figs 6B , 7B ); endites serrula present in single row on anterolateral margin, setae sparse. Abdomen ( Figs 5A, B ) ovoid, length 0.72, width 0.65, slightly elongate oval in dorsal view (AW/AL ≈ 0.9), dorsum soft portions white, without particular color pattern but obvious herringbone band dorsally; pedicel tube short, unmodified; book lung small, round. Spinnerets ( Figs 5B ) small, numerous setae on second spigot on anterior spinnerets, with tiny dark spots forming circular band around spinnerets. Legs ( Figs 5A −C ) yellow, with sparse setae, femur IV thickened, wider than femora I −III.

Genitalia ( Figs 5F, G , 6C −F , 7C, D ): In ventral view, anteriorly with triangular sclerotized plate and with roughly oval, median dark spot at its base, above epigastric slit. In dorsal view, posterior plate (Pp) bowl-shaped, covering 3/4 of AUS, posterior part connected with short and strong lateral extension (Ex2), with procurved arc shape anteriorly; AUS long and broad, visible through cuticle, with well developed lateral, strongly recurved Pr; apically with a thin cylindrical, T-shaped sclerite. Receptaculum not visible in our sample but probably fused at base of AUS.

Male: Unknown.

Distribution. Known only from Jiangxi Province ( Fig. 11 ).

Figures

FIGURE 11. Collection localities for Orchestina apiculata sp. nov., O. bialata sp. nov. and O. multipunctata sp. nov. in China.

FIGURES 5 A − G. Orchestina bialata sp. nov., female paratype (OON 8). A. Habitus, dorsal view; B. As previous, ventral view, the arrow shows the dark circular band around spinnerets; C. Prosoma, dorsal view; D. As previous, frontal view; E. As previous, ventral view; F. Genital area, ventral view; G. As previous, cleared, dorsal view. Scale bars: A − C, E, 0.2 mm; D, 0. 1 mm; F, 50 µm; G, 20 µm

FIGURES 6 A − F. Orchestina bialata sp. nov., SEMs of female paratype. A. Chelicerae (OON 9), frontal view, slightly lateral. B. Mouthparts (OON 10), ventral view. C. Genitalia (OON 9), dorsal view. D. Genitalia (OON 10), posterior plate moved a little. E. Genitalia (OON 11), posterior plate removed. F. As previous, posterior plate, ventral view. Abbreviations: AUS, anterior uterine sclerite; Ex 2, dorsolateral extension; PP, posterior plate; Pr, lateral protrusion. Scale bars: A, F, 0.1 mm; B − E, 20 µm.

FIGURES 7 A − D. Orchestina bialata sp. nov., female paratype (OON 11). A. Chelicerae, frontal view; B. Mouthparts, ventral view; C. Genitalia, ventral view; D. As previous, dorsal view. Abbreviations: AUS, anterior uterine sclerite; Ex 2, dorsolateral extension; PP, posterior plate; Pr, lateral protrusion. Scale bars: A, B, 0.1 mm; C, 50 µm; D, 20 µm.