Tylorida ventralis ( Thorell, 1877 )

Sankaran, Pradeep M., Malamel, Jobi J., Joseph, Mathew M. & Sebastian, Pothalil A., 2017, On the genus Tylorida Simon, 1894 with the first record of the genus Atelidea Simon, 1895 from India (Araneae: Tetragnathidae, Leucauginae), Zootaxa 4353 (2), pp. 294-326 : 310-311

Tylorida ventralis ( Thorell, 1877)

( Figs 1E–F , 2C , 7G–I , 12H–I , 15A–F , 16A–J , 17A–O , 18A–O , 19A–E )

Meta ventralis Thorell, 1877: 423 (Description of male and female)

Argyroepeira ventralis Thorell, 1887: 138 . Workman, 1896: 55, plate 55 (Brief somatic description and description of web; illustration of female)

Leucauge ventralis Pocock, 1904: 800 , plate 66, fig. 3a–c (Illustration of male and female). Anopas ventralis Archer, 1951: 7 , figs 8–9 (Transfer of male and female from Leucauge to Anopas ). Tylorida ventralis Chrysanthus, 1975: 31 , figs 117–120 (Transfer of male and female from Anopas to Tylorida ; illustration of

male and female).

[See World Spider Catalog (2017) for complete list of citations].

Leucauge pondae Tikader, 1970: 44 , fig. 25a–d (Description and illustration of male and female); 1982: 89. figs 175–178 (Description and illustration of male and female). Holotype female (Regd. No. 3221/18) and allotype male (Regd. No. 3222/18), both poor in condition, from INDIA: West Sikkim: Bang of Great Rangit river; B. K. Tikader leg.; 20-09-1959; deposited in ZSI, Kolkata, EXAMINED. New Synonymy.

Material examined: INDIA, Kerala: Kottayam, Kumarakom Bird Sanctuary (9o37'46.97''N, 76o25'25.56''E), 13 m alt., 25 February 2013 , M. S. Pradeep & M. J. Jobi leg., from web, by hand: 1 male, 2 females, 1 subadult female ( ADSH1004514 ). Alappuzha, Pathiramanal Island (9o37'08.27''N, 76o23'23.86''E), 0 m alt., 13 March 2013 , M. S. Pradeep & M. J. Jobi leg., from web, by hand: 9 males, 15 females ( ADSH1004515 ). Kollam, Kulathupuzha (8o54'06.37''N, 77o03'51.70''E), 134 m alt., 29 August 2013 M. S. Pradeep leg., from web, by hand: 5 males, 8 females ( ADSH1004516 ). Kottayam, Pala, Areeppara in Edappady , 9o42'35.62''N, 76o42'48.42''E, 27 m alt., 12 May 2014, M.S. Pradeep leg., from web, by hand: 5 males, 7 females (3 females with egg sac) ( ADSH1004517 ). Kottayam, Kanakappalam in Erumely , 9o27'16.08''N,76o50'43.54''E, 101 m alt., 23 August 2014, M. S. Pradeep leg., from foliage, by hand: 1 female with egg sac (ADSH1004518). Alappuzha, Perumbalam, 9o50'54.13''N, 76o21'39.00''E, 10 m alt., 30 November 2015, M. J. Jobi & Jimmy Paul leg., from web, by hand: 1 male, 1 female, 1 subadult male (ADSH1004519). Ernakulam, Thalacode, 10o03'03.22''N, 76o44'27.12''E, 60 m alt., 25 December 2015, Aswathy leg., from web, by hand: 1 female (ADSH1004520).

Justification of the synonymy. Tikader (1970) described L. pondae based on one female (holotype), three females (paratype) and one male (allotype) collected from the Bank of Great Rangit river, West Sikkim. The description was published in his Spider Fauna of Sikkim and was supported by four text figures- prolateral view of male pedipalp, dorsal view of female habitus, retrolateral view of female opisthosoma and ventral view of epigynum ( Tikader 1970: fig. 25a–d). He redescribed the species in 1982 with four text figures – dorsal view of female habitus, dorso-lateral view of left male pedipalp, ventral view of epigynum and female internal genitalia ( Tikader 1982: figs 175–178). Later, Sebastian and Peter (2009) provided brief morphological descriptions of both male and female, but presented neither illustrations of the male and female reproductive structures nor information on its possible synonymy with T. ventralis . In the original illustrations of Tikader, the shape of CDBP ( Tikader 1970: fig. 25d, Tikader 1982: fig. 176) and the outline of epigynal plate ( Tikader 1970: fig. 25c, Tikader 1982: fig. 177) and the female internal genitalia ( Tikader 1982: fig. 178) suggest a synonymy of L. pondae with T. ventralis . Detailed examination of the types of L. pondae ( Fig. 19A–E ) suggests that these specimens have all diagnostic, both somatic and genitalic, features of T. ventralis . The species L. pondae should be regarded as a junior synonym of T. ventralis .

Note. Tylorida ventralis seems to exhibit colour polymorphism, a well-known example of phenotypic diversity, as well as intraspecific variation, both somatic as well as genitalic. We have found two distinct colour morphs of T. ventralis , which show conspicuous variation in female opisthosoma colouration: Silver morph ( Figs 1E , 15A, D , 16A, E, F ) has silvery abdomen due to silver spots on dorsal and lateral opisthosoma. Yellow morph ( Figs 1F , 16J ) has dorsal and lateral opisthosoma ornamented with deep yellow spots. In both the morphs, the venter of opisthosoma is generally dull brown with a broad median black patch, cephalothorax is brown, legs are brown with black annulations and posterior extremity of opisthosoma has paired black spots (an identification feature of L. pondae suggested by Tikader). The epigyna of both the morphs are also similar with slight intraspecific variations (compare Fig. 18A–F, J–O with G–I). In the field, Silver morph is commonly encountered than the Yellow morph, which is rare to find. The species is known for its intraspecific variation in genitalia ( Jäger & Praxaysombath 2009: figs 24, 28–31, 33, 36–37). Unlike Jäger and Praxaysombath (2009), we have noted both somatic as well as genitalic variations in T. ventralis . Based on the morphology of posterior opisthosoma of females, we have suggested our female specimens to belong to three varieties: variety I, without a ‘caudal tubercle’ ( Fig. 16H–J ), variety II, with an ‘indistinct caudal tubercle’ ( Fig. 15D–F ) and variety III, with a ‘distinct caudal tubercle’ ( Fig. 16C–E ). Tikader (1982) also mentioned similar modification of ‘indistinct caudal tubercle’ of female opisthosoma. The opisthosoma of males, however, in all these three varieties is provided with an ‘indistinct caudal tubercle’ ( Figs 15A–C , 16A–B, F–G ). It is observed that the variety I females and its males are smaller in size (male body length 4.22–4.62, female body length 5.18–5.43) than that of variety II and variety III females (body length 7.16–7.98) and their corresponding males (body length 6.19–6.27). We have also observed high level of variations in both the male and female genitalia of all the three varieties. The pedipalpi exhibit variations in size, orientation and course of sperm ducts (e.g., Fig. 17A–D, F–I, K–N ). The epigyna and internal female genitalia vary significantly from specimen to specimen (e.g., Fig. 18A–O ). However, the morphology of male chelicerae ( Fig. 17E, J, O ) of all the three varieties clearly indicates that these all are intraspecific variants and belonging to the same species, T. ventralis .

Figures

FIGURE 1A–F. Field photographs of Tylorida spp. A Female Tylorida flava sp. nov. from Illithodu, Ernakulam (ADSH100454); B–C Tylorida marmorea (Pocock, 1901) comb. nov. from Ponmudi, Trivandrum (ADSH100458): B Male; C Female;D Femaleof Tylorida striata (Thorell, 1877)from MuriyadKol Wetland, Thrissur,Kerala (CATE99462); E–FFemales of Tylorida ventralis (Thorell, 1877): E Silver morph from Pathiramanal Island, Alappuzha (ADSH1004515); F Yellow morph from Kanakappalam, Kottayam (ADSH1004518). Photo credit A & E, Pradeep M. Sankaran; B & C, Jimmy Paul; D, Nafin K.S.; F, Dhruv A. Prajapati.

FIGURE 2A–C. Field photographs of Tylorida spp. mating pairs. A Tylorida marmorea (Pocock, 1901) comb. nov. from Ponmudi,Trivandrum (ADSH100458); B Tylorida striata (Thorell,1877) from Parambikulam TigerReserve,Palakkad,Kerala (CATE99461); Tylorida ventralis (Thorell, 1877) from Wayanad Wildlife Sanctuary, Wayanad, Kerala (CATE99463). Photo credit A, Jimmy Paul; B & C, Nafin K.S..

FIGURE 7A–I. Male left leg I of Tylorida spp. A–C Tylorida marmorea (Pocock, 1901) comb. nov.: A tibia, prolateral; B metatarsus, prolateral; C tarsus, prolateral; D–F Tylorida striata (Thorell, 1877): D tibia, prolateral; E metatarsus, prolateral; F tarsus, prolateral; G–I Tylorida ventralis (Thorell, 1877): G tibia, prolateral; H metatarsus, prolateral; I tarsus, prolateral. Scale bars A–C, E, H, I, 0.5 mm; D, G, 1 mm; F, 0.2mm.

FIGURE 12A–K. Left chelicerae of Tylorida spp. and Orsinome cf. vethi (Hasselt, 1882). A–E Left chelicerae of Tylorida marmorea (Pocock, 1901) comb. nov.: A Male (High altitude form), prolateral; B Female (High altitude form), prolateral; C Male (Low altitude form), prolateral; D Female (Low altitude form), prolateral; E Orginal drawings of male and female cheliceraeadopted from Gravely(1921) without modification; F–G Left chelicerae of Tylorida striata (Thorell, 1877):F Male, retrolateral; G Female, prolateral; H–I Left chelicerae of Tylorida ventralis (Thorell, 1877): H Male, prolateral, arrow indicates tiny tubercle; I Female,ventro-retrolateral;J–K Left cheliceraeof Orsinome cf.vethi: J Male, retrolateral; K Female,prolateral. Scale bars A–B, H–I, 1 mm; C–D, 0.5 mm; F–G, 0.2 mm; J–K, 0.5 mm; E, not to scale.

FIGURE 15A–F. Tylorida ventralis (Thorell, 1877): variety I, female with indistinct caudal tubercle from Edappady, Kottayam.A–C Male habitus: A dorsal; B ventral; C retrolateral; D–F Female habitus:D dorsal; E ventral, F retrolateral.Scale bar A–F, 2 mm.

FIGURE 16A–J. Tylorida ventralis(Thorell, 1877):variety II, female with distinct caudal tubercle (Figs A–E) and variety III, female without caudal tubercle (Figs F–J).A–B, F–G Male habitus:A, F dorsal; B,G retrolateral; C–E, H–J Femalehabitus:C, H dorsal; D prolateral;E, I–J retrolateral.A–Dfrom Pathiramanal Island, Alappuzha, Efrom Kumarakom,Kottayam, F–Ifrom Perumbalam, Alappuzha, J from Kulathupuzha, Kollam.Scale bar A–J, 2 mm.

FIGURE 17A–O. Tylorida ventralis (Thorell, 1877): male left pedipalp illustrating intraspecific variations and left chelicerae. A–E variety I from Edappady, Kottayam:A–D Left pedipalp:A prolateral; B ventral; C retrolateral; D dorsal; E Left chelicera, prolateral; F–J variety II from Pathiramanal Island, Alappuzha: F–I Left pedipalp: F prolateral; G ventral; H retrolateral; I dorsal; J Left chelicera, prolateral; variety III from Perumbalam, Alappuzha: K–N Left pedipalp: K prolateral; L ventral; M retrolateral; N dorsal; O Left chelicera, prolateral. Scale bars A–D, 0.5 mm; E, 1 mm;F–O, 0.5 mm.

FIGURE 18A–O. Tylorida ventralis (Thorell, 1877): female genitalia illustrating intraspecific variations. A–F variety II, female with distinct caudal tubercle (A–C from Kumarakom, Kottayam and D–F from Kulathupuzha, Kollam): A–B, D–E Epigyna, ventral; C, F Internal female genitalia, dorsal; G–I, M–O variety III, female without caudal tubercle (G–I another female from Kulathupuzha, Kollam and M–O from Perumbalam, Alappuzha): G–H, M–N Epigyna, ventral; I, O Internal female genitalia, dorsal; J–L variety I, female with indistinct caudal tubercle (from Edappady, Kottayam): J–K Epigyna, ventral; L Internal female genitalia, dorsal. Scale bars A–C, J–L, 0.2 mm; D–I, M–O, 0.5 mm.

FIGURE 19A–E. Leucauge pondae Tikader, 1970 (=Tylorida ventralis (Thorell, 1877)). A, C–D Male allotype (Reg. No. 3222/18, ZSI, Kolkata): A Male habitus, dorsal; C Left pedipalp, prolateral; D Same, retrolateral; B, E Female holotype (Reg. No.3221/18, ZSI, Kolkata):B Femalehabitus, dorso-prolateral; E Epigynum, ventral.Scale bars A–B, 2 mm; C–E, 0.2 mm.