Mosu tanjia new species

Figs 7–12, 26

Type material: Holotype: male (IZCAS), Huyun Cave (23°21.607´N, 105°02.047´E; altitude 1464 m), Tanjiawan Village, Tiechang Town, Malipo County, Yunnan, China, 9 August 2010, Z.Y. Yao, X.X. Wang and C.Q. Wu. Paratypes: 3 males and 5 females, same data as holotype (IZCAS).

Etymology. The specific epithet is a noun in apposition taken from an abbreviated from of the collection locality.

Diagnosis. Female Mosu tanjia n. sp. can be distinguished from M. nujiang Miller, Griswold & Yin, 2009 by the absence of an epigynal scape and the vaulted trajectory of sclerotized copulatory ducts above spermathecae (Figs 9 B, 12B). Males can be distinguished from M. dayan by a short, spur-like cymbial process (Figs 8 C, 10C, 11C) and bowl-shaped tibia (Figs 8 A–B, 11A–B) in male pedipalp.

Description. Male: Holotype (Figs 7 A–C), total length 0.86. Prosoma 0.38 long, 0.39 wide, 0.30 high. Carapace of prosoma dark brown, rounded, with concave anterior margin (Fig. 10 A). Cephalic pars abruptly raised. Ocular area situated at apex, black. Eight eyes in two rows. AME black, others white, with black ring. From dorsal view, AER and PER slightly recurved. ALE and PLE contiguous. All eyes nearly round, subequal to in size. Clypeus 0.18 high, 3.0 x AME diameter; ALE separated by about 3.5 x its diameter from anterolateral edge of carapace. Chelicerae darkish yellow, shorter than endites in length. Labium grey, fused to sternum. Endites pale yellow, longer than wide, with serrula. Sternum 0.27 long, 0.25 wide, heart-shaped, with a pair of triangular pale spots on shoulder position and a cruciate pale stripe in midline. Legs greyish, proximally light and distally fuscous in each segment. Legs formula: I-II-IV-III. Leg measurements: I 1.63 (0.52, 0.18, 0.36, 0.27, 0.30); II 1.32 (0.41, 0.16, 0.29, 0.20, 0.27); III 0.95 (0.27, 0.13, 0.18, 0.14, 0.23); IV 1.13 (0.36, 0.13, 0.23, 0.20, 0.21). Leg I with a ventral sclerotized spot on femur subdistally, and with a mesial clasping spine on metatarsus prolaterally. Each leg with a dorsal seta on patella distally, a proximal seta and 3 dorsal trichobothria on tibia. Opisthosoma 0.50 long, 0.54 wide, 0.63 high. Subround dorsally, black, with a pair of white spots on abdominal dorsum, irregular white strips circled abdominal lateral surface. Ventral abdomen less colored than dorsal.

Pedipalp large, brown (Figs 8 A–C; 11A–C). Femur, patella and tibia without modifications. Tibia wide, bowlshaped, covered with long setae along the distal margin. Cymbium translucent, wrinkled membranous, with a spurlike cymbial process. A row of orderly apical setae on cymbial fold. Bulb nearly globose. Subtegulum smooth, strongly sclerotized. Tegulum rugose, translucent. Spermatic ducts can be seen through translucent tegulum. Embolus long, coiled into two loops, and extending to apex of cymbium.

Female: Total length 1.02 (one of paratypes) (Figs 7 D–F). Prososma 0.45 long, 0.43 wide, 0.25 high. Coloration and shape same as but cephalic pars lower than in male. As eyes arrangement as in male. AER recurved and PER slightly procurved. Clypeus 0.11 high, equal to 2.0 x AME diameter. ALE separated by about 2.3 x AME diameter from anterolateral verge of carapace. Chelicerae, labium and endites same as in male. Sternum 0.28 long, 0.29 wide, modified pattern like as in male. Legs formula: I-II-IV-III. Leg measurements: I 1.71 (0.55, 0.20, 0.38, 0.29, 0.30); II 1.45 (0.45, 0.18, 0.32, 0.23, 0.27); III 1.07 (0.30, 0.14, 0.20, 0.18, 0.25); IV 1.38 (0.45, 0.16, 0.29, 0.23, 0.25). Subdistally Leg I and II with a ventral sclerotized femoral spot (Fig. 7 E). Setae and trichobothria on each leg as in male. Opisthosoma 0.70 long, 0.68 wide, 0.57 high. Coloration and patterns as in male.

Epigynum area rugose, covered with long setae (Fig. 10 D). Epigynal scape absent. Spermathecae ovoid, sclerotized copulatory ducts connected with lateral corner of spermathecae. Fertilization ducts short, deriving from inner corner of spermathecae. Membranous copulatory ducts rugose, occupied large area around spermathecae (Figs 9 A–B, 12A–B).

Variation. The total length ranges from 0.73 to 0.86 in males (n = 4) and from 0.88 to 1.02 in females (n = 5).

Distribution. Known only from the type locality (Fig. 26).