Neriene birmanica (Thorell, 1887)

Xu, Xin, Jie, Liu & Chen, Jian, 2010, Ambengana Millidge & Russell-Smith, 1992, a synonym of Neriene Blackwall, 1833 (Araneae, Linyphiidae), ZooKeys 52, pp. 1-8 : 3-7

Neriene birmanica (Thorell, 1887) Figs 112

Linyphia birmanica Thorell, 1887: 99 (f).

Bathyphantes kashmiricus Caporiacco, 1935: 167, pl. 2, fig. 12 (m).

Neriene kashmirica van Helsdingen, 1969: 261, figs 359-360 (m).

Neriene birmanica van Helsdingen, 1969: 265, figs 361-363 (f).

Neriene birmanica Chen, Zhu & Chen, 1989: 1, figs 1-10 (mf).

Neriene birmanica Chen, Gao, 1990: 99, figs 124 a–j (mf).

Neriene birmanica Song, Zhu & Chen, 1999: 188, figs 108 G–H, Q (mf).

Ambengana complexipalpis Millidge, Russell-Smith, 1992: 1387, figs 52-55 (mf), syn. n.

Material examined.

CHINA: 1 ♂, 3 ♀, Sichuan Province, Panzhihua City, Miyi County, 10.07.1981 Gao J.C.; 1 ♂, 1 ♀, same locality, Chen X.E.; 2 ♂, 3 ♀, Yunnan Province, Dehong DaiJingpo Autonomous Prefecture, Ruili City, 16.09.2000, Chen, W. H. and Liu, F. X.; 2 ♂, 6 ♀, Yunnan Province, Lincang City, Zhenkang County, Nansan Town, 14.09.2000, Chen, W. H. and Liu, F. X.; 1 ♀, Yunnan Province, Honghe Hani and Yi Prefecture, Luchun County, 2.09.2000, Chen, W. H. and Liu, F. X.; 3 ♂, 7 ♀, Yunnan Province, Xishuangbanna Dai Autonomous Prefecture, Menghai County, Daluo Town, 9.09.2000, Chen, W. H. and Liu, F. X.; 1 ♂, same province and prefercture, Menghai County, 10.09.2000, Chen, W. H. and Liu, F. X.; 1 ♀, Yunnan Province, Honghe Hani and Yi Prefecture, Jinping Miao, Yao and Dai Autonomous County, 30.08.2000, Chen, W. H. and Liu, F. X.; 1 ♀, Yunnan Province, Pu'er Prefecture, Jiangcheng Hani and Yi Autonomous County, 25.09.2000, Chen, W. H. and Liu, F. X.

Diagnosis.

Tibia not fusiform, with few spines; paracymbium with narrow distal arm tapering to a sharp tip; hook-shaped tip of distal part of median apophysis curved in ventral direction; transversal and terminal sclerites never present; lateral depressions of the epigyne small and superficial, this species belongs to the peltata-species group (van Helsdingen 1969). It can be distinguished from other members of the peltata-group species by the tiny paracymbium (Fig. 4), the sword-shaped embolic tip (Figs 4, 6), the broad and short terminal apophysis with about one coil (Figs 2, 5), the translucent spot at either side of the uniquely trapeziform atrium opening, the superficially depressed area at either side next to lateral translucent spots (Fig. 9), and the scape forming a rounded mesal projection and spiral grooves of about two coils in the female (Figs 10, 11).

Description.

Male: Total length: 2.78. Carapace: 1.22 long, 0.94 wide. Abdomen: 1.54 long, 0.98 wide. Carapace brown, unmodified. Eyes subequal. AER recurved, AME-AME shorter than AMEd, AME-ALE slightly longer than AMEd; PER straight, PME-PME about PMEd, PME-PLE slightly longer than PMEd; ALE and PLE juxtaposed. Chelicerae brown, stridulatory ridges absent, promargin of fang groove with three teeth, median tooth largest;, retromargin with three small teeth, first bigger than others. Lengths of legs: I 5.36 (1.47+1.58+1.52+0.79), II 4.90 (1.33+1.43+1.38+0.76), III 4.08 (1.19+1.16+1.08+0.65), IV 4.41 (1.25+1.21+1.29+0.66). Each tibia, patella and femur with two dorsal spines. Tm I: 0.20. Tm IV absent. Abdomen cylindriform, without tubercle; colour and pattern as in Fig. 1.

Patella short, with long spine dorsally. Tibia shorter than cymbium, with several long spines on lateral and ventral surfaces, and one prodorsal, two retrodorsal trichobothria. Paracymbium tiny, long and slender, U-shaped, slightly membranous (Fig. 4). Median apophysis long, slender in lateral view, with dorsal tip hook-shaped (Figs 4, 7). Lamella well-developed, with four projections: lateral one and posterior one long, lateral one with sharp, membranous end, posterior one with blunt end; anterior one broad, blunt; dorsal one short (Fig. 3). Terminal apophysis simple, broad and short, strongly membranous from prolateral view, with about one coil (Figs 2, 5). Embolus simple, perpendicularly curved at half length, with a sword-shaped end (Figs 4, 6).

Female: Total length: 2.86. Carapace: 1.14 long, 0.69 wide. Abdomen: 1.71 long, 1.30 wide. Carapace brown, unmodified. Eyes subequal. AER recurved, AME-AME shorter than AMEd, AME-ALE slightly shorter than AMEd; PER straight, PME-PME shorter than PMEd, PME-PLE about equal with PME-PME; ALE and PLE juxtaposed. Chelicerae brown, stridulatory ridges absent, promargin of fang groove with three teeth, median tooth largest; retromargin with three equal teeth. Lengths of legs: I 5.27 (1.44+1.61+1.44+0.78), II 4.60 (1.26+1.42+1.23+0.69), III 3.17 (0.93+0.94+0.79+0.51), IV 4.47 (1.37+1.27+1.21+0.62). Each tibia, patella and femur with two dorsal spines. Tm I: 0.22. Tm IV absent. Abdomen oval, without tubercle, the colour and patch see Fig. 8.

In ventral view, atrium opening small, trapeziform. Lateral depression present (Fig. 9). Scape arising from dorsal wall, short, with slightly rounded tip, and with small semi-covered depression on ventral surface (Fig. 10). Spermathecae as long as wide; spiral grooves started from entrances situated in the middle of the ventral wall of either atrium to the apical turning-points, with about two coils; fertilized ducts started from spermathecae, with (about) two coils; turning points situated laterally; spermathecae long and slender, situated laterally (Fig. 11).

Remarks.

Although we didn’t examine the type speciemens of Ambengana complexipalpis , the tiny paracymbium, the sword-shape embolic tip, broad and the short terminal apophysis, the uniquely trapeziform atrium opening shown in the original illustrations ( Millidge and Russell-Smith 1992 figs 52-54) leave no doubts that our identification is correct. The original illustration of the spermathecae by Millidge and Russell-Smith (1992, fig. 55) is rather simplified and shows some differences with the specimen of Neriene birmanica we have examined (cf. Fig. 11). However, such the difference does not affect our identification.

Distribution:

Southeast Asia (India, Kashmir, Myanmar, China, Indonesia) (Fig. 12).