Orsinome vethi ( Hasselt, 1882 )

Caleb, John T. D., Ghosh, Dibyajyoti & Kumar, Vikas, 2018, On two new synonyms of the orb-weaving spider Orsinome vethi (Hasselt, 1882) (Araneae, Tetragnathidae), Zootaxa 4444 (3), pp. 342-346 : 342-346

Orsinome vethi ( Hasselt, 1882) ( Figs 1 –9, 16–32)

Pachygnatha vethii Hasselt, 1882: 32 (Description of ♂).

Orsinome vethi Thorell, 1890: 209 (Description of ♀); Simon, 1895: 736, figs. 798–800.

Leucauge lygisma Wang, 1991: 154 , f. 10–12 (Misidentification; description and illustration of ♂); Song, Zhu & Chen, 1999: 216, f. 121J, 122G–H, 130N–O (Misidentification; description and illustration of ♂).

Orsinome vethi Zhu, Song & Zhang, 2003: 295 , figs. 165A–F, 166A–G, pl. XA–D (Description and illustration of ♂ & ♀); Jäger & Praxaysombath, 2009: 33, figs. 19–23 (Illustration of ♀); Álvarez-Padilla & Hormiga, 2011: 791, figs. 100A–G, 101A–H, 102A– F, 103A–F, 104A–D (Description and illustration of ♂ & ♀); Sankaran et al., 2017: 319, f. 12J–K, 20A–F, 21A–G (Illustration of ♂ & ♀)

Orsinome listeri Gravely, 1921: 449 , f. 7c (Misidentification; description of ♂&♀ and illustration of ♂). Type material kept at NZC-

ZSI examined. New synonymy.

Labulla nepula Tikader, 1970: 21 , figs. 13a–d (Misidentification; description and illustration of ♂&♀). Holotype female, allotype

male and paratype female kept at NZC-ZSI examined. New synonymy.

Type material of Labulla nepula Tikader, 1970 : ♀ (holotype) (NZC-ZSI-A/305; 3248/18); ♂ (allotype) (NZC-ZSI-A/ 307; 3249/18); ♀ (paratype) (NZC-ZSI-A/306; 3250/18) from the Bank of Great Rangit River , 20 September 1959, West Sikkim; all leg. B. K. Tikader.

Type material of Orsinome listeri Gravely, 1921: 2 ♀♀ & 2♂♂ (NZC-ZSI-9978/17) from Peshok (=Pashok), Darjeeling district, Eastern Himalayas, 26 May – 14 June 1916, West Bengal; all leg. F. H. Gravely.

AdditiONal material: 1♀ (ZSI-CDT-AA191) from Balipara (26.825714° N, 92.775494° E) 84 m, Assam, 14 November 2015; 1 subadult ♂ (ZSI-CDT-AA204), Bishwanathghat (26.658769° N, 93.175767° E), 84 m, Assam, 8 November 2015, leg. Shantanu Kundu; 1♂ (ZSI-CDT-AA1312) & 1♀ (ZSI-CDT-AA1313) from Ashaley river bed (27.011198° N, 88.770108° E) 692 m, Neora Valley, West Bengal, 0 8 March 2017, leg. Dibyajyoti Ghosh.

JustiFicatiON OF syNONymy OF Labulla nepula . L. nepula Tikader, 1970 was described based on three specimens (holotype female, allotype male and a paratype female) from Sikkim, India. Tikader (1970) has been critically assessed for assigning several species to wrong genera ( Brignoli 1976; Breitling 2015). Hormiga & Scharff (2005) reasoned precisely that this species was misplaced in the genus Labulla Simon, 1884 . Detailed examination of the type material revealed that the species was both misidentified as well as misclassified. The species actually belongs to the tetragnathid genus Orsinome Thorell, 1890 . The general morphology and abdominal pattern of the holotype female and allotype male show striking resemblance to specimens illustrated by Zhu et al. (2003) and Sankaran et al. (2017) (cf. figs. 165A & C in Zhu et al., 2003 and figs. 20A–F in Sankaran et al., 2017 with Figs. 1, 2 & 6–8 herein). The epigynum of the holotype was not dissected and is intact. It clearly shows a medial common copulatory opening (cf. fig. 21 in Jäger & Praxaysombath, 2009 with Fig. 9 herein). The male palp shows the characteristic diagnostic features such as the long and well-sclerotized embolus with its distal part resting on the subtegulum and the dorsomedian process on the cymbium ( Álvarez-Padilla & Hormiga, 2011) (cf. figs. 166E–G in Zhu et al., 2003 and figs. 21A–D in Sankaran et al., 2017 with Figs. 3–5 herein). Based on these characters both the female holotype and the male allotype are identified as O. vethi and L. nepula is thus considered a junior synonym of the former.

The paratype female however does not belong to Orsinome but rather fits in the genus Tylorida Simon, 1894 . The general morphology, color pattern and genitalia match with that of T. ventralis ( Thorell, 1877) ( Figs 10–15 ). The abdomen lacks a posterior caudal tubercle ( Figs 13–14 ) and falls into the category, variety I of T. ventralis (sensu Sankaran et al. 2017: figs. 16H–J). The epigynum morphology corresponds well with the epigynum of variety I as illustrated by Sankaran et al. (2017) (cf. Fig. 15 herein with figs. 18J–L in Sankaran et al., 2017).

JustiFicatiON OF syNONymy OF Orsinome listeri . Gravely (1921) described O. listeri based on specimens from Peshok and Singla, Darjeeling district, West Bengal, India. The species is known only from its original description. Detailed examination of the type material revealed that the species unambiguously matches O. vethi in general morphology (cf. figs. 165A & C in Zhu et al., 2003 and figs. 20A–F in Sankaran et al., 2017 with Figs. 16–17 herein); the male cheliceral dentition with three promarginal teeth (one large and two small), two retromargin teeth, a large tubercle and a tiny tubercle at the base (cf. fig 7c in Gravely 1921, fig 166 D in Zhu et al,. 2003 and figs. 12 J in Sankaran et al., 2017 with Figs. 20–22 herein); the male palpal structure (see characters mentioned above; Figs 24–28 ) and the epigynum ( Figs 29–31 ); the internal duct system ( Fig 32 ) is identical to those illustrated in Zhu et al. (2003; fig 165 F) and Sankaran et al., (2017; fig 21 G). Based on these observations, we consider O. listeri as a junior synonym of O. vethi .

DistributiON. The species has a wide oriental distribution known from India, China, Vietnam, Laos, Malaysia, Sumatra, Java, to Flores ( WSC, 2018).

Figures

FIGURES 1–5. Male allotype of Labulla nepula Tikader, 1970 (= Orsinome vethi Hasselt, 1882). 1, Dorsal view. 2, Lateral view. 3, Left palp, prolateral view. 4, Same, ventro-lateral view. 5, Same, ventral view. 6–9. Female holotype of Labulla nepula Tikader, 1970 (= Orsinome vethi Hasselt, 1882). 6, Dorsal view. 7, Ventral view. 8, Lateral view. 9, Epigynum, ventral view. Scale bars 1–2, 6–8, 1 mm; 3–5, 9, 0.2 mm.

FIGURES 10–15. Female paratype of Labulla nepula Tikader, 1970 (= Tylorida ventralis Thorell, 1877). 10, Carapace, dorsal view. 11, Chelicerae, ventral view. 12, Abdomen, dorsal view. 13, Same, lateral view. 14, Same, ventral view. 15, Epigynum, ventral view. Scale bars, 10–15, 0.5 mm.

FIGURES 16–32. Type material of Orsinome listeri Gravely, 1921 (= Orsinome vethi Hasselt, 1882). 16, Male, dorsal view. 17, Female, dorsal view. 18, Male, front view. 19, Same, lateral view. 20, Left chelicera, ventro-retrolateral view. 21, Same, prolateral view. 22, Same (ZSI-CDT-AA-1312). 23, Male left palp, anterior view. 24, Same, prolateral view. 25, Same, latero-ventral view. 26, Same, ventral view. 27, Same, latero-ventral view. 28, Same, dorsal view. 29, Epigynum, ventral view. 30, Same, additional type material. 31, Epigynum, ventral view (ZSI-CDT-AA-1313). 32, Vulva, dorsal view (ZSI-CDT-AA-1313). Scale bars, 17, 2.0 mm; 16, 18, 1 mm; 19, 0.5 mm; 20–32, 0.2 mm.