Siamspinops banna Lin & Li, 2022

Lin, Yejie, Zhao, Huifeng, Koh, Joseph K H & Li, Shuqiang, 2022, Taxonomy notes on twenty-eight spider species (Arachnida: Araneae) from Asia, Zoological Systematics 47 (3), pp. 198-270 : 233-238

Siamspinops banna Lin & Li , sp. nov. ( Figs 35–37 )

Diagnosis. Males of the new species are similar to S. formosensis (Kayashima, 1943) by the T-shaped conductor and embolus arising from the 9-o’clock-position of the tegulum ( Yu et al., 2019, figs 1–17), but can be distinguished by having the median apophysis folded outward in a pocket shape (vs. median apophysis straight in S. formosensis ), the dorsal retrolateral tibial apophysis is two times longer than the ventro-retrolateral tibial apophysis (vs. 1.5 times in S. formosensis ) and the terminus of the dorsal retrolateral tibial apophysis is enlarged and racket shaped (vs. flat in S. formosensis ). Females of the new species resemble those of S. spinescens Dankittipakul & Corronca, 2009 by the long accessory lobe of spermatheca, but in the former species the epigynal pockets are contiguous and median septum absent (vs. epigynal pocket separate and median septum present in S. spinescens ).

Description. Male (holotype, Fig. 37A ). Total length 4.26; carapace 1.99 long, 2.53 wide; abdomen 2.25 long, 2.10 wide. Carapace yellow, lateral margins yellowish-brown. Eye sizes and interdistances: AME 0.12, ALE 0.08, PME 0.13, PLE 0.18, AME–AME 0.13, AME–ALE 0.28, PME–PME 0.46, PME–PLE 0.23, ALE–PLE 0.15. Chelicerae yellow, with 3 retromarginal teeth and 1 promarginal tooth; labium and maxillae yellow; sternum yellow, lateral margins brown; legs pale yellow, with greyish spots. Leg measurements: I 8.13 (2.45, 2.87, 1.93, 0.88), II 11.46 (3.63, 4.18, 2.61, 1.04), III 11.16 (3.79, 4.00, 2.43, 0.94), IV 8.35 (3.11, 2.58, 1.88, 0.78). Leg formula 2341. Abdomen yellow with brown pattern.

Palp ( Fig. 35 ). Patella without apophysis. Palpal tibia two times longer than patella. Retrolateral tibial apophysis with two branches, ventro-retrolateral tibial apophysis small, slightly curved, dorsal retrolateral tibial apophysis two times longer than ventro-retrolateral tibial apophysis, terminus enlarged. Bulb relatively round, with basolateral excavation below embolic base. Conductor T-shaped. Embolus filiform.

Female (IZCAS-Ar43292, Fig. 37B ). Total length 6.00; carapace 2.34 long, 2.50 wide; abdomen 3.73 long, 2.57 wide. Eye sizes and interdistances: AME 0.13, ALE 0.08, PME 0.16, PLE 0.23, AME–AME 0.14, AME–ALE 0.33, PME–PME 0.50, PME–PLE 0.25, ALE–PLE 0.15. Leg measurements: I 5.02 (1.75, 1.98, 0.86, 0.43), II 7.35 (2.51, 3.19, 1.01, 0.64), III 7.13 (2.28, 3.13, 1.07, 0.65), IV 7.23 (2.76, 2.57, 1.25, 0.65). Leg formula 2431. Habitus similar to that of male.

Epigyne ( Fig. 36 ) with epigynal pocket, copulatory opening conspicuous, arc-shaped. Copulatory duct inconspicuous. Spermathecal head longer than spermatheca, terminus expanded. Spermatheca strongly convoluted, with 8 coils; fertilization ducts leaf shaped.

Material examined. Holotype ♂ (IZCAS-Ar43287), Yunnan, Xishuangbanna Dai Autonomous Prefecture, Mengla County, Menglun Township , G213 road, Banyan tree (21.9015°N, 101.2837°E, elev. 579 m), 28 November 2009, G. Tang and Z. Yao leg. Paratypes. 1♂ (IZCAS-Ar43288), Yunnan, Xishuangbanna Dai Autonomous Prefecture, Mengla County, Menglun Township , G213 road, Secondary forest (21.9076°N, 101.2792°E, elev. 644 m), 20 November 2009, G. Tang and Z. Yao leg. ; 1♂ (IZCAS-Ar43289), Yunnan, Xishuangbanna Dai Autonomous Prefecture, Mengla County, Menglun Township , G213 road, Bamboo plantation (21.8941°N, 101.2829°E, elev. 589 m), 26 November 2009, G. Tang and Z. Yao leg. ; 1♂ (IZCAS-Ar43290), Yunnan, Xishuangbanna Dai Autonomous Prefecture, Mengla County, Menglun Township , G213 road, Bamboo plantation (21.9064°N, 101.2800°E, elev. 627 m), 22 November 2009, G. Tang and Z. Yao leg. ; 1♀ (IZCAS-Ar43291), Yunnan, Xishuangbanna Dai Autonomous Prefecture, Mengla County, Menglun Township , Primary tropical seasonal rain forest (21.9172°N, 101.2750°E, elev. 558 m), 1–15 February 2007, G. Tang leg. ; 1♀ (IZCAS-Ar43292), Yunnan, Xishuangbanna Dai Autonomous Prefecture, Mengla County, Menglun Township , G213 road, Bamboo plantation (21.8940°N, 101.2823°E, elev. 580 m), 3 December 2009, G. Tang and Z. Yao leg.

Distribution. Known only from the type locality.

Etymology. The specific name is a noun in apposition taken from the type locality.

Figures

Figure 35. Siamspinops banna Lin & Li, sp. nov., holotype male, left palp. A. Ventral view; B. Retrolateral view. Abbreviations: C— conductor; dRTA—dorsal retrolateral tibial apophysis; E—embolus; MA—median apophysis; vRTA—ventroretrolateral tibial apophysis. Scale bars=0.3mm.

Figure 36. Siamspinops banna Lin & Li, sp. nov., paratype female. A. Epigyne, ventral view; B. Vulva, dorsal view. Abbreviations: CO—copulatory opening; EP—epigynal pocket; FD—fertilization duct; S—spermatheca; SH—spermathecal head; UE—uterus externus. Scale bars=0.2mm.

Figure 37. Habitus of Siamspinops banna Lin & Li, sp. nov., dorsal view.A. Male; B. Female. Scale bars=1.0mm.