Ischnothyreus auritus, Tong, Yanfeng & Li, Shuqiang, 2012

Tong, Yanfeng & Li, Shuqiang, 2012, Four new species of the genus Ischnothyreus from Hainan Island, China (Araneae, Oonopidae), Zootaxa 3352, pp. 25-39 : 26

Ischnothyreus auritus sp. nov.

( Figs 1–2 , 11 )

Type material: 1 male Holotype ( IZCAS Ar 19317), sifting leaf litter, China: Hainan, Wuzhishan Natural Reserve, Shanye Tavern, 911 m, 18°54.418´N, 109°40.647´E, April 26, 2011, leg. Yuanye Zhou; 2 female paratypes ( IZCAS Ar 19317), same data as holotype; 1 male and 5 female paratypes ( IZCAS Ar 19327), sifting leaf litter, China: Hainan, Limushan Natural Reserve, Qulinggulin Garden, 654 m, 19°10.686´N, 109°44.490´E, August 12, 2007, leg. Chunxia Wang; 2 female paratypes ( IZCAS Ar 19336), sifting leaf litter, China: Hainan, Wuzhishan Natural Reserve, plank in tropical forest, August 7, 2007, leg. Chunxia Wang; 1 female paratype ( IZCAS Ar 19338), sifting leaf litter, China: Hainan, Wuzhishan Natural Reserve, tropical forest, April 28, 2011, leg. Yuanye Zhou; 1 female paratype ( IZCAS Ar 19337), sifting leaf litter, China: Hainan, Jianfengling Natural Reserve, Ecology Protection Station, 820 m, 18°44.415´N, 108°51.802´E, May 17, 2011, leg. Yuanye Zhou; 1 male paratype ( IZCAS Ar 19331), sifting leaf litter, China: Hainan, Yinggeling Natural Reserve, Yinggezui, around waterfall, 622 m, 19°03.037´N, 109°44.899´E, May 8, 2011, leg. Yuanye Zhou.

Etymology: The specific name means ‘ear-shaped’ in Latin, and refers to the shape of the palpal apophysis; adjective.

Diagnosis: The female resembles that of Ischnothyreus serpentinum Saaristo, 2001 , but can be distinguished by the larger atrium ( Figs 2 C, D), the shape of the postepigastric scutum and the larger dorsal scutum. The male resembles that of I. danum Kranz-Baltensperger, 2011 , but differs in lacking the brush-like process at the base of the cheliceral fangs ( Figs 1 F, G, 2G).

Description: Male (holotype). Total length 1.55 mm. Carapace: orange-brown, with brown egg-shaped patches behind eyes, oval in dorsal view, pars cephalica strongly elevated in lateral view, surface and sides strongly reticulate. Eyes: six, in one group, well developed, ALE largest, PME and PLE nearly equal sized; posterior eye row straight from above, procurved from front. Mouthparts: chelicerae slightly divergent, with strongly sclerotized hook-like process (hlp) and a prominent laminar process (lp) at base of fangs; fang groove with a few small and one larger denticles ( Figs 1 F, G, 2G). Anterior margin of labium not indented at middle. Anteromedian tip of endites with one strong, tooth-like projection. Abdomen: book lung covers dark, large, elliptical. Posterior spiracles not connected by groove. Pedicel tube short, unmodified, scutum extending far dorsal of pedicel. Dorsal scutum covering about total of abdomen, about equal to the abdomen width, not fused to epigastric scutum. Epigastric and postepigastric scutum well sclerotized, pale orange, fused. Leg spine formula: femur I with 2 prolateral and 1 small retrolateral spine, tibia I with 4 pairs, metatarsus I with 2 pairs of long ventral spines. Spination of leg II similar to leg I except femur with only one prolateral spine. Legs III and IV spineless. Genitalia: Sperm pore situated at level of anterior spiracles. Palp strongly sclerotized, trochanter with ventral projection (vp); patella about as long as femur, not enlarged; cymbium brown, not fused with bulb, bulb brown, more than 2 times as long as cymbium, stout, tapering apically, with one large ventral protuberance (vpr), at the bending site with a lobe (l), distal part of bulb with an ear-shaped apophysis (esa) ( Figs 2 A, B, E, F).

Female (paratype). Total length 1.96 mm. As in male except as noted. Carapace: without any pattern, pars cephalica slightly elevated in lateral view. Mouthparts: chelicerae and endites unmodified. Abdomen: dorsal scutum covering about 2/3 of abdomen, about 2/3 of abdomen width. Postepigastric scutum rectangular, not fused to epigastric scutum, with short posteriorly directed lateral apodemes (a) ( Fig. 2 D). Genitalia: the posterior margin of the epigastric scutum is lined with numerous needle-like setae; at the middle of the anterior edge of the postepigastric scutum runs a dark, strongly winding tube posteriorly (wt), ending in a large bell-shaped atrium (bsa) ( Figs 2 C, D, H, I).

Distribution: Known only from Hainan Island.

Figures

FIGURE 1. Ischnothyreus auritus sp. nov., A – G, male; H – K, female. A, H, habitus, dorsal view; B, J, habitus, lateral view; C, I, habitus, ventral view; D, K, prosoma, frontal view; E, prosoma, ventral view; F, G, left chelicera, anterior and posterior views. hlp, hook-like process; lp, laminar process. Scales: A, B, C, H – J = 0.4 mm; D, E, K = 0.2 mm; F, G = 0.1 mm.

FIGURE 2. Ischnothyreus auritus sp. nov. A, E, left male palp, prolateral view; B, F, left male palp, retrolateral view; C, H, female genital area, ventral view; D, I, female genital area, dorsal view; G, male left chelicera, anterior view. a, apodeme; bsa, bell-shaped atrium; esa, ear-shaped apophysis; hlp, hook-like process; l, lobe; lp, laminar process; vp, ventral projection; vpr, ventral protuberance; wt, winding tube. Scales: A, B, D – I = 0.1 mm; C = 0.2 mm.

FIGURE 11. Localities of four new Ischnothyreus species from Hainan Island, China.