Mysmena lulanga, Lin, Yucheng & Li, Shuqiang, 2016

Lin, Yucheng & Li, Shuqiang, 2016, Mysmenidae, a spider family newly recorded from Tibet (Arachnida, Araneae), ZooKeys 549, pp. 51-69 : 56-58

Taxon classification Animalia Araneae Mysmenidae

Mysmena lulanga sp. n. Figs 5, 6, 7, 8, 9, 10

Type material.

Holotype: male (IZCAS), CHINA: Tibet Autonomous Region, Nyingchi County, the east of Lulang Town (29°41.984'N, 94°43.657'E; Elevation: 3480 m), 14 July 2013, L.H. Lin leg. Paratypes: 1 male and 7 females (IZCAS), same data as holotype; 1 male and 10 females (IZCAS), Nyingchi County, the east of Lulang Town (29°41.449'N, 94°43.605'E; Elevation: 3530 m), 14 July 2013, L.H. Lin leg., all types by manual sampling.

Etymology.

The specific name derives from the type locality. The epithet is a noun in apposition.

Diagnosis.

Male distinguished by the cymbial conductor with two distal macrometae (Figs 6 A–B, 7C). Female distinguished from other congeners by the ovate spermatheca and the vulva without membranous copulatory duct or/and fertilization duct (Figs 8B, 9 A–B). Compared with other Chinese Mysmena species, the new species and Mysmena baoxingensis Lin & Li, 2013 have the most similar in configuration of palp and inner form of epigynum (see Lin and Li 2013a: figs 14 A–E, 15 A–D), but male differs from the latter by the shorter, wider embolus (Figs 6 A–B, 7 A–B), the two cymbial distal macrosetae (Figs 6B, 7A, 7C), and female by the near egg-shaped spermatheca (Figs 8B, 9 A–B), the upswept fertilization ducts (Figs 8B, 9B) and the tapering, non-sclerotized scape (Figs 8A, 9A). Distinguished from the Vietnamese species Mysmena maculosa and Mysmena tamdaoensis (Lin & Li, 2014) by the lack of cymbial spur and the female abdomen without posterior projection, or by a simple embolus and the epigynum with a long scape. Further distinguished from other Mysmena species in Sulawesi ( Baert 1988), New Guinea ( Baert 1982, 1984; Forster 1959), Samoa ( Marples 1955), North America ( Lopardo and Dupérré 2008) and Latin America (e.g. Baert and Maelfait 1983; Gertsch 1960; Gertsch and Davis 1936; Levi 1956) by the shorter embolus and the lack of membranous copulatory duct (Figs 6 A–B, 9B).

Description.

Male (holotype). Somatic characters see Fig. 5 A–C. Coloration: Prosoma darkish, ocular area black. Sternum black, with a pale longitudinal stripe centrally. Opisthosoma black dorsally, with three pair of white speckles, one large centrally and two small marginally, white pigment stripe at the lateral and posterior, black ventrally. Femora of legs pale yellow, other segments pale proximally, darkish distally.

Measurement: Total length 0.71. Prosoma 0.33 long, 0.35 wide, 0.31 high. Opisthosoma 0.45 long, 0.43 wide, 0.50 high. Clypeus 0.09 high. Sternum 0.24 long, 0.25 wide. Length of legs: I 1.18 (0.38, 0.16, 0.24, 0.18, 0.22); II 1.04 (0.32, 0.14, 0.22, 0.16, 0.20); III 0.79 (0.23, 0.12, 0.14, 0.13, 0.17); IV 0.94 (0.29, 0.13, 0.18, 0.15, 0.19).

Prosoma: Carapace near round. Cephalic pars elevated, sharply vertical forward and slope backward. Clypeal margin concave. Ocular area at apex. Eight eyes in two rows. AME black, others white. ALE and PLE contiguous. AME smallest, ALE equal to PME in size. ALE=PME>PLE>AME. ARE slightly precurved, PRE slightly recurved. Chelicerae pale, small, shorter than endites (Fig. 5C). Endites with tiny serrula. Labium rectangular, wider than long, fused to sternum. Sternum cordiform, plump.

Legs: formula: I-II-IV-III. Leg I with a prolateral-mesial metatarsal clasping macroseta. Sclerotized femoral spot present at leg I and II. Patellae I–IV with a dorsal seta distally. Tibiae I–IV with a dorsal seta proximally. Tibiae I and II with 3 trichobothria, but 4 on tibia III and IV. Metatarsi I–IV with only one trichobothrium.

Opisthosoma: Globular dorsally. Spinnerets dark, the anteriors larger than the posteriors. Colulus tiny, black. Anal tubercle darkish.

Palp (Figs 6 A–D, 7 A–C): Femur long, ca. 3 times as long patella. Patella short, with a few setae. Tibia swollen, cup-shaped, covered with long setae on distal margin ventrally and dorsally (Fig. 6 A–D). Cymbium membranous, wide, arisen from tibial margin prolaterally (Figs 6C, 7D). Cymbial groove distinct, rugose (Figs 6 A–B, 7C). Paracymbium small semiround, undevolped (Fig. 7C). Distal lobe of cymbium auriform (Fig. 7C). Setae on cymbial fold irregular arrange (Figs 6B, 7A, 7C). Cymbial conductor horn-shaped, with two strong cymbial distal marocsetae at apex (Figs 6B, 7A). Conductor (or tegulum) smooth, globular (Figs 6B, 7 A–B). Spermatic duct visible through subtegulum (Figs 6 A–B, 7 A–B). Embolus wide, strongly sclerotized. Embolar end sharp (Fig. 7 A–B).

Female

(one of paratypes). Somatic characters see Fig. 5 D–F. Coloration: Same as in male.

Measurement: Total length 0.95. Prosoma 0.38 long, 0.40 wide, 0.35 high. Opisthosoma 0.66 long, 0.60 wide, 0.67 high. Clypeus 0.08 high, slightly lower than in male. Sternum 0.26 long, 0.27 wide. Length of legs: I 1.25 (0.41, 0.17, 0.26, 0.19, 0.22); II 1.10 (0.35, 0.16, 0.22, 0.17, 0.20); III 0.87 (0.26, 0.14, 0.15, 0.14, 0.18); IV 1.04 (0.33, 0.15, 0.21, 0.16, 0.19).

Prosoma: Carapace near pear-shaped. Cephalic pars lower than in male. Eyes pattern, chelicerae, endites and sternum as in male.

Legs: Chaetotaxy and number of trichobothria same as in male, except for leg I without metatarsal clasping macroseta. Sclerotized femoral spot present at leg I and II. Leg formula: I-II-IV-III.

Opisthosoma: Globose dorsally. Spinnerets grey, the anteriors larger than the posteriors. Colulus small, black, tongue-shaped.

Vulva (Figs 8 A–B, 9 A–B): Epigynum large, weakly sclerotized. Epigynal area covered with short setae (Fig. 8A). A long, tapering scape arising from the middle posi tion between spermathecae, not from epigynal posteromargin mesially (Figs 8A, 9A). Spermathecae large, strongly sclerotized, near egg-shaped (Figs 8B, 9B). A translucent, broad anterior genital plate lain beneath spermathecae (Figs 8B, 9B). Copulatory ducts short, derives from ventral-posterior position of spermathecae ventrally, and connected with anterior corner of genital plate (Figs 8B, 9 A–B). Fertilization ducts short, upswept, connected with dorsal-posterior position of spermathecae (Fig. 8B).

Distribution.

Known only from the type locality (Fig. 10).