Singaporemma bifurcata, Lin & Li, 2010

Lin, Yucheng & Li, Shuqiang, 2010, New armored spiders of the family Tetrablemmidae from China, Zootaxa 2440 (1), pp. 18-32 : 26-28

Singaporemma bifurcata sp. nov.

Figs 29–37 , 50

Type material: Holotype: male ( IZCAS), Hejiao Cave ( T.: 15 ºC; H.: 90%; Alt.: 695 m), Guihua Village , Wenquan Town, Suiyang County [28°15´N, 107°17´E, Guizhou, China], 12 May 2007, Y.C. Lin and J. Liu leg. Paratypes: 7 males and 14 females, same data as holotype ( IZCAS) .

Other material examined. CHINA: Yunnan: 4 males and 5 females, Tongxuan Cave ( T.: 16 ºC; H.: 85%; Alt.: 1870 m), Danfengshan hill, Shizong County [24°50´N, 103°59´E], 22 March 2007, Y.C. Lin and J. Liu leg. ; 1 female, Zhiyun Cave ( T.: 15ºC; H.: 90%; Alt.: 1756 m), Tianshengqiao Village , Shilin County [24°51´N, 103°18´E], 24 March 2007, Y.C. Lin and J. Liu leg. ( IZCAS) .

Etymology. From Latin bifurcata = furcate, in reference to the shape of embolus of male pedipalp.

Diagnosis. This new species resembles S. halongense Lehtinen, 1981 , but differs by 1) the asymmetrically furcate embolus of peidpalp, 2) the transversely striated modification on palpal femur in male, 3) the shape of prolate epigynal pit, and 4) the subround central process in female.

Description. Male: 1.01–1.16. Coloration orange. Prosoma length 0.50–0.54, width 0.41–0.44, maximal height 0.41–0.43. Opisthosoma length 0.79–0.84, width 0.57–0.60. Six eyes oval, subequal in size. PME absent. Anterior eye row slightly recurved as viewed from above. Ocular area black. Cephalic pars sleek, higher slightly than ocular area, without decoration. Dorsal shield of prosoma retiform in center, wrinkled along margin distinctly. Chelicerae normal, anterior surface without obviously process ( Fig. 34 ). Sternum centrally sleek, marginally retiform. Leg measurements: I 1.22 (0.40, 0.12, 0.30, 0.20, 0.20); II 1.14 (0.38, 0.12, 0.26, 0.18, 0.20); III 1.04 (0.32, 0.12, 0.22, 0.18, 0.20); IV 1.40 (0.44, 0.14, 0.36, 0.22, 0.24). Leg formula: 4-1-2-3. Except for patella, all sections of legs transversely striated. Of opisthosoma dorsal scutum oval and sleek. Ventral plates finely markings. Postgetinal plate precurved slightly, wider than preanal plate. Preanal plate width about equal to 2.5 times its length.

Male pedipalpal femur transversely striated. Patella short, no modified. Tibia swollen. Pedipalpal bulb subround. Embolus slightly flexuous, its root originating from prolaterally mesial surface of bulb, embolic end furcated ( Figs 35–37 ).

Female: 1.16–1.21. Prosoma length 0.52–0.55, width 0.43–0.45, maximal height 0.42–0.44. Opisthosoma length 0.87–0.92, width 0.60–0.64. Except for pedipalp, all decorations same as in male. Leg measurements: I 1.24 (0.42, 0.12, 0.30, 0.20, 0.20); II 1.18 (0.38, 0.12, 0.28, 0.20, 0.20); III 1.08 (0.32, 0.10, 0.26, 0.20, 0.20); IV 1.44 (0.46, 0.12, 0.38, 0.24, 0.24). Leg formula: 4-1-2-3. Of opisthosoma dorsal scutum larger than in male, but similar in shape. Postgenital plate with a row of plumose setae, its posterior rim overlapped anterior rim of preanal plate. Genital area covered with plumose setae ( Fig. 32 ).

Epigynal pit is small and flat. Epigynal fold indiscernible. Central process round and membranous, almost covered sclerotized entire inner vulval plate dorsally. Postgenital plate fold thin and short ( Fig. 33 ).

Natural history. This spider mainly lives in the dark caves, and they usually are found under small stones and rocks.

Distribution. Except for type location of Guizhou, this species is also found in two caves in Yunnan ( Fig. 50 ).

Figures

FIGURE 50. Locality records of tetrablemmid species in China.

FIGURES 29–37. Singaporemma bifurcata sp. nov. 29–31 Male prosoma (29 dorsal, 30 lateral, 31 ventral view); 32 Female opisthosoma, ventral view; 33 Female genital area (KOH-treated), ventral view; 34 Male left chelicera, anterior view; 35–36 Male left pedipalp (35 prolateral, 36 retrolateral view); 37 Male pedipalpal embolus, prolateral view. Scales: 0.1 mm