Ischnothyreus corollacous sp. nov.

(Figure 1)

Type material: Holotype: Female (IZCAS AR 19389), Laos, Champasak Province, Tad Fane Resort, 15º10.944'N, 106º07.606'E, elevation 955 meters, November 21, 2012, leg. S. Li. Paratype: 1 female (IZCAS AR 19407), Laos, Champasak Province, Pak Song, Tad Gneuang Waterfall, 15º10.944'N, 106º08.166'E, elevation 952 meters, November 22, 2012, leg. S. Li.

Etymology: The specific name means “corolla” in Latin, and refers to the shape of the female genitalia; adjective.

Diagnosis: The new species can be distinguished from the other congeneric species by the shape of the female genital area.

Description: Female (holotype). Total length 2.21; carapace 0.96 length, 0.78 width; abdomen 1.45 length, 0.92 width. Habitus as in Figs 1 A, B. Carapace: brown, broadly oval in dorsal view, pars cephalica slightly elevated in lateral view, surface and sides strongly reticulate (Figs 1 C, D). Eyes: six, in one group, well developed, ALE largest, PME and PLE nearly equal sized; posterior eye row procurved from both above and front. Mouthparts (Fig. 1 E): chelicerae slightly divergent, without prominent basal process. Anterior margin of labium not indented at middle. Anteromedian tip of endites unmodified. Femur of palp with three ventral spines (Fig. 1 F). Abdomen: Pedicel tube short, unmodified, scutum extending far dorsal of pedicel. Book lung covers light, large, elliptical. Dorsal scutum covering about 1/3 of abdomen, about 1/3 of abdomen width. Epigastric scutum weakly sclerotized, postepigastric scutum not fused to epigastric scutum, with short posteriorly directed lateral apodemes. Leg formula: femur I with 3 prolateral and 2 small retrolateral spines, tibia I with 4 pairs, metatarsus I with 2 pairs of long ventral spines. Leg II spination is similar to leg I except femur with only 2 prolateral and 1 retrolateral spines. Legs III and IV spineless. Genitalia (Figs 1 G–K): the posterior margin of the epigastric scutum is lined with numerous needle-like setae; at middle of the postepigastric scutum is a dark, corolla-like structure visible (cls in Fig. 1 J).

Male: Unknown.

Distribution: Known only from the type locality.