Orchestina apiculata, 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 : 432-434

Orchestina apiculata sp. nov.

Figures 1−4 , 11 .

Type material. Holotype male: China, Hunan Province: Changsha City, Yuelu District, Yuelu Mountain, forest, 28.1914°N, 112.9384°E, 337m, 14.IV.2011, Haiyang Tan and Keke Liu leg. (OON 1). Paratypes: 3 males (OON 2−4) and 2 females (OON 5−6), same data as holotype.

Etymology. The specific name is a Latin adjective, meaning “apiculate” and referring to the fine and long tip of the embolus.

Diagnosis. Males of the new species resemble to those of O. tubulata Tong & Li, 2011 (especially the shape of the enlarged palpal tibia and the oval bulb) ( Tong & Li 2011), but they can be distinguished by the ratio of the palpal tibia (L/W = 1.53) ( Figs 2A, B , 3D, E , 4C, D ), by the long and thin embolus and the position of the cymbium and by the absence of strong setae on the distal margin of the endites. Moreover, males of the new species also resemble to O. flagella Saaristo & Marusik, 2009 , sharing a similar palpal tibia and a slender embolus with comparable basal part ( Saaristo & Marusik 2009). However, they can be distinguished from this species by the pattern of the prosoma, the presence of endites with serrula, the ratio L/W of the tibia as mentioned above, the oval bulb ( Figs 2A, B , 3D, E , 4C, D ), and the longer fine embolus (almost as long as the enlarged palpal tibia). The female genital area ( Figs 2C, D , 3I , 4E −G ) of this new species is completely different from that of O. tubulata and O. flagella .

Description. Male. Habitus as in Fig. 1A . Total length 1.00−1.20. Holotype total length 1.12, carapace ( Figs 1A , 3A, B ) length 0.53, width 0.50, orange, broadly oval in dorsal view (CW/CL ≈ 0.93), pars cephalica slightly domed in lateral view, anteriorly narrowed to 0.5 times its maximum width, with few tiny dark spots on lateral margin and scattered setae on median part, without color pattern. Eyes: PME circular, touching; diameters: ALE 0.05, PME 0.08, PLE 0.05, PME 1.6 times PLE; ALE–PME touching, PLE–PME separated from less than PME radius. Clypeus ( Figs 1D , 3B ) margin unmodified, curved downwards in frontal view, quite steeply in lateral view, with two groups of seven setae on laterally rounded corners near ALE. Sternum ( Fig. 1E ) longer than wide, heartshaped, surface smooth, yellow; setae sparse and scattered, needle-like. Mouthparts ( Figs 1D, E , 3B, C , 4A, B ): Chelicerae straight, pale yellow, anterior face unmodified, with u-shaped space at base, without group of strong apical setae, base of fang with pair of feather-like setae ( Fig. 3C ); labium sub-circular, yellow, slightly elevated in the median part in ventral view, not fused to sternum, with pair of thin flattened, leaf shaped setae on posterior half ( Figs 1C , 3B ); endites convergent anteriorly, serrula present in single row on anterior lateral margin, with 14−20 setae on apical margin. Abdomen ( Fig. 1A ) globular, yellow-brown, length 0.58, width 0.49, slightly elongate oval in dorsal view (AW/AL ≈ 0.84), with three herringbone bands, tiny brown spots, and abundant setae dorsally; book lung small, round; pedicel tube short, unmodified. Legs yellow, with abundant setae, femur IV thickened, wider than femora I −III. Genitalia ( Figs 2A, B , 3D, E , 4C, D ): Palp: stout, yellow; femur distal part abruptly narrowed; patella shorter than femur, attached to tibia sub-proximally; tibia strongly enlarged (TW/TL ≈ 0.64), ovoid, with numerous setae on prolateral side; cymbium curved, with scattered setae on dorsal side; bulb yellowish white, ellipsoidal, with spherical projection on the ventral medial part, 1.5 times as long as its maximum width; embolus as long as femur, long and fine, needle-like, bent inwards to labium, forming an angle of about 100° with the axis of bulb

.

Female. Habitus as in Figs 1B, C . Total length 1.25, carapace ( Figs 1B , 3F ) length 0.55, width 0.42, yellow, strongly elongated oval in dorsal view (CW/CL ≈ 0.76), pars cephalica slightly elevated in lateral view, anteriorly narrowed to 0.5 times its maximum width, with scattered setae and few tiny sepia spots on dorsal part forming a net-shaped pattern. Eyes diameters: ALE 0.04, PME 0.05, PLE 0.04, PME 1.25 times ALE and PLE; ALE −PME touching, PLE −PME separated from less than PME radius. Clypeus ( Figs 3F, G ) margin unmodified, with two groups of two long setae on the laterally rounded corners. Mouthparts ( Figs 1C , 3G, H ): Chelicerae yellow, base of fang as in male; Labium ( Figs 1C , 3H ), as long as wide, with 8 setae on anterior margin, flattened leaf shaped setae absent, with two lateral setae and four central setae delimiting a quadrangle. Sternum ( Fig. 1C ), yellowish white, with numerous needle-like setae and few tiny yellow spots along margins. Abdomen ( Figs 1B, C ): length 0.67, width 0.55, globular, slightly elongated oval in dorsal view (AW/AL ≈ 0.82), with three herringbone bands, tiny brown spots, and numerous setae in dorsal view. Spinnerets short, setae abundant, with a circular dark band around the base. Legs ( Figs 1B, C ) yellow, with numerous setae, femur IV thickened, wider than femora I −III. Genitalia ( Figs 2C, D , 3I , 4E −G ): in ventral view, genital structures visible through cuticle strongly sclerotized and darker posteriorly, with two paramedian pockets near epigastric slit. In dorsal view, anterior uterine sclerite (AUS) broad oblong, anteriorly with short lateral protrusions (Pr), posteriorly narrowed, with two long dorsolateral extensions (Ex1) with widened angular apex, with cylindrical sclerite in medial part. Receptaculum not visible in our sample, but probably fused with AUS anteriorly.

Distribution. Known only from Changsha ( Fig. 11 ).

Figures

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

FIGURES 1 A − E. Orchestina apiculata sp. nov. A. Male holotype, dorsal view; B. Female (OON 5) paratype, dorsal view; C. As previous, ventral view; D. Male holotype, habitus, frontal view, the arrow shows the u-shaped space at bases of chelicerae; E. As previous, prosoma, ventral view. Scale bars: 0.2 mm.

FIGURES 2 A − D. Orchestina apiculata sp. nov. A. Male holotype, left palp, prolateral view; B. As previous, retrolateral view; C. Female (OON 5) paratype, genitalia, ventral view; D. As previous, cleared, dorsal view. Abbreviations: AUS, anterior uterine sclerite; Ex 1, lateral extension; Po, pocket; Pr, protrusions. Scale bars: A, B, 0.2 mm; C, D, 0.1 mm.

FIGURES 3 A − I. Orchestina apiculata sp. nov., SEMs of male and female paratypes. A. Male (OON 2), dorsolateral view; B. Male (OON 2) prosoma, dorsolateral view, the white arrow shows the group of seven setae in front of AER; C. Male (OON 3) mouthparts, ventral view, the white arrow shows the flattened, leaf shaped setae, the black arrows show the pair of feather-like setae at base of fang; D. Male (OON 2) left palp, retrolateral view; E. Same as previous, detail; F. Female (OON 5) prosoma, dorsal view; G. Female (OON 5) chelicerae, frontal view, slightly dorsal; H. Female (OON 5) mouthparts, ventral view, the white arrows show the two lateral setae, the black stars show four central setae, the black arrows indicate the pair of feather-like setae at base of fang; I. Female (OON 5) genitalia, dorsal view. Abbreviations: AER, anterior eye row; AUS, anterior uterine sclerite; Pr, lateral protrusions. Scale bars: A, 0.2 mm; B, D, 0.1 mm; E, 50 µm; F, 30 µm; C, G − I, 10 µm.

FIGURES 4 A − G. Orchestina apiculata sp. nov. A. Male holotype, chelicerae, frontal view, the arrow shows the u-shaped space at base of the chelicerae; B. Male holotype, mouthparts, ventral view; C. Male holotype, left palp, prolateral view; D. As previous, retrolateral view; E. Female (OON 5) paratype, genitalia, ventral view; F. As previous, dorsal view; G. As previous, posterior view. Abbreviations: AUS, anterior uterine sclerite; Ex 1: lateral extension; Pr, lateral protrusion. Scale bars: A, B, 0.2 mm; C − G, 0.1 mm.