Nepalella troglodytes Liu, sp. nov. Figs 2 A & 3–9

Material examined. Holotype male (SCAU n1), China, Guizhou, Guiyang City, Xifeng County, Hejiadong Village, Cave Hejia Dong, 27°02’31’N, 106°31’40’’E, 1200 m a.s.l., 13.VII.2013, leg. Mingyi Tian, Weixin Liu, Haomin Yin & Sunbin Huang.

Paratypes: 1 male (SEM n2), 2 females (SCAU n3), same data as in holotype . 1 male, 1 female (SCAU n4), same County, Mushan Village, Cave Zhangkou Dong, 27°04’10’’N, 106°32’55’’E, 1300 m a.s.l., 2.XII.2014, leg. Mingyi Tian & Jingli Cheng.

Other material. 1 male, 1 female (ZMUM), 1 male, 1 female (SCAU n5), Guizhou, Qiannan Zizhizhou, Longli County, Cave Feilong Dong, 26°27’11’’N, 106°58’46’’E, 1200 m a.s.l., 15.I.2014, leg. Mingyi Tian & Jingli Cheng . 1 male, 2 females (SCAU n6), China, Guizhou, Qiannan Zizhizhou, Fuquan County, Cave Sanlou Dong, 26°56’46’’N, 107°18’47’’E, 1280 m a.s.l., 2015-V-2, leg. Mingyi Tian & Jingli Cheng .

Etymology. To emphasize this new species is a presumed troglobite; noun in apposition.

Diagnosis. Differs from congeners by 3+3 macrochaetae on metaterga 5–26 being short, and only male legs 3– 5 distinctly incrassate, legs 6–7 nearly normal, while male tarsi 3–11 are equipped with special foliate setae ventrally; and the anterior gonopod sternum lacks a median lobe.

Description. Length ca 20–25 (♂) or 21.5–26 mm (♀), midbody width 1.5–2.1 (♂) or 1.8–2.3 mm (♀). Color in life (Figs 2 A, 6, 8) pale, only metaterga 15–26 slightly light yellow; eye patches light brownish.

Body with 30 segments. Head width = segment 10–18> 6–9> 5> 4> 3> 2> collum; posterior to segment 19, body gradually tapering towards telson (Fig. 2 A).

Head densely setose, clypeolabral region slightly convex. Eye patches composed of 4–6 convex ocelli (Fig. 6 B).

Antennae (Fig. 3 C) very long and slender, reaching behind posterior (♂) or anterior (♀) margin of body segment 6 when stretched posteriorly; antennomere 7 (= antennomere 8) with four apical cones on stalks (Fig. 3 C– D).

Gnathochilarium typical, lamellae linguales large (Fig. 3 A).

Mandible with a movable external tooth with two cusps, and an internal tooth with six cusps; ten pectinate lamellae, intermediate area hairy; molar plate flat, anterior fringe with hand-like pieces (Fig. 3 B).

Collum normal (for heterochordeumatoideans), obcordate in shape. Integument smooth and shining (Fig. 2 A). Metatergal setation 3+3, typical, placed on minute knobs; only macrochaetae on collum and metaterga 2–4 moderately long, macrochaetae on metaterga 5–26 rather short (Fig. 5 A). Stricture between pro- and metazona shallow (Figs 5 A, 6A). Paraterga poorly-developed, very small dorsolateral bulges in anterior part of body (Fig. 6 A).

CIX (15) = 0.52; MIX (15) = 1.0; MA (15) = 120°; PIX (15) impossible to evaluate due to insufficiently welldeveloped paraterga (Fig. 5 A). Axial suture distinct, pallid (Fig. 6 A). Limbus very inconspicuous, regularly microdentate.

Legs long and slender (Figs 6, 8), slightly longer in male, about 2.0–2.5 times as long as midbody height. Legs 1 and 2 slightly reduced, tarsi with usual ventral brushes, but without papillae. Tarsi 3–11 (rarely 10) with conspicuous, abundant, foliate setae (fs) ventrally (Fig. 3 E–F, I). Male legs 3–5 distinctly incrassate (Fig. 3 E), legs 6–7 nearly normal. Male legs 10 with coxal glands (cg) (Fig. 3 H); prefemur 10 with a very small basal hump. Male prefemur 11 with a large, basal, digitiform outgrowth (d) ventrally (Fig. 3 I–J). Claws simple, long (Fig 3 E, G, I).

Anterior gonopods (leg-pair 8) very strongly reduced, sternum without process; coxites (cxi) long and slender (Figs 4 A, 5B, 9B). Posterior gonopods (Figs 4 B–C, 5C–D, 9C–D) hypertrophied, with a large colpocoxite (c), tip divided and folded; with a bush-like structure (b) at base on caudal face; telopoditomere 1 (t1) strongly enlarged, telopoditomere 2 (t2) small, sometimes with a vestigial segment apically.

Vulva (Figs 4 D, 9E) rounded, with a small process on operculum (op).

Intraspecific variation. Specimens from Cave Feilong Dong showing the posterior gonopod telopodites strongly reduced, retaining only telopoditomere 1 (t1) (Fig. 7). Specimens from Cave Sanlou Dong show longer 3+3 macrochaetae on the metaterga (Fig. 8), and differences in CIX (15) = 0.63; MIX (15) = 2.56; MA (15) = 115° (Fig. 9 A).

Remarks. N. troglodytes sp. nov. is widely distributed in the Guizhou Province, with specimens recorded from four different localities (Fig. 24). Although some specimens show slight variations, the gonopods are relatively stable in all specimens observed.

Based on the clearly unpigmented body and reduced eyes, combined with the extremely long legs and antennae, N. troglodytes sp. nov. seems to be a troglobite.