Eutrichodesmus spinatus sp. n.

Figs 6–8

Material: Holotype male (SCAU), China, Hunan Prov., Sidu Town, Sidu Caves, 28.06.2011. leg. Tian Mingyi, Gao Qi & Sun Feifei (CHIhn11-LWX01). Paratypes: 1 male, 2 females (SCAU), same locality, together with holotype.

Name: To emphasize the gonopod telopodite carrying a conspicuous, spinigerous, lateral, distofemoral process (dp).

Diagnosis: Differs from congeners by the volvation being apparently imperfect because the paraterga are mostly only slightly declivous; the metaterga behind collum with three transverse isostictic rows of large rounded tubercles; the gonopod telopodite with a conspicuous, spinigerous, lateral, distofemoral process (dp) at about midway while the acropodite is simple and very strongly curved.

Description: All characters as in E. digitatus sp. n., except as follows.

Length of adults of both sexes ca 6.5-8.0 mm, width 1.2-1.5 mm. Holotype ca 7.5 mm long and 1.5 mm wide. Coloration uniformly pallid (Fig. 6 A).

Conglobation pattern typical of “ Doratodesmidae ”, but volvation apparently imperfect because of paraterga mostly being only slightly declivous, leaving small lacunae laterally even when body is maximally enrolled.

Antennae (Fig. 3 C) rather short and stout. Collum with five regular transverse rows of large round tubercles (Fig. 6 B). Limbus not microcrenulate (Fig. 6 D). Dorsum behind collum with three transverse isostictic rows of large rounded tubercles, each row with about 10 tubercles, but dorsum only with few setae. Paratergal surface coarse, without tubercles; paraterga slightly declivous, broad, 3- or 4-lobate laterally, nearly parallel to level of venter, caudolaterally at base with one distinct impression, thus somewhat interrupting the contour of a convex dorsum (Figs 6 A-B). Paraterga 2 strongly enlarged, with three lobulations anterolaterally. Paraterga 3 and 4 slightly shorter than others, each with three lobulations anterolaterally. Pleurosternal ridges wanting.

Sterna between ♂ coxae 6, 7 and 9 much wider. Legs rather long and relatively slender, reaching tips of paraterga; femora and tarsi longest, subequal in length; some setae with microdenticulations (Fig. 6 E).

Gonopods (Figs 3 F-H) very simple. Coxae subquadrate, large, microtuberculate and abundantly setose ventrolaterally. Telopodite longer than coxite, slender throughout, setose in its basal half, with a conspicuous, spinigerous, lateral, distofemoral process (dp) at about midway. Acropodite very strongly curved ventrad; seminal groove terminating subapically with a hairpad.

Remarks: This is a typical “doratodesmid”, possibly a troglobite.