Theridion odisha Prasad, Caleb, Tyagi & Kumar, 2019

Prasad, Priya, Tyagi, Kamoud, Caleb, John T. D. & Kumar, Vikas, 2019, A new species of the cob web spider genus Theridion from India (Araneae: Theridiidae), Ecologica Montenegrina 26, pp. 108-117 : 109-112

Theridion odisha Prasad, Caleb, Tyagi & Kumar sp.n.

Figs 1–6 , 24

https://zoobank.org/ urn:lsid:zoobank.org:act:F7E58000-51C9-498A-B449-C13B17343542

Type. Holotype female (ZSI-CDT-AA-1694), India: Odisha: KIIT campus, Bhubaneshwar (20.3547°N, 85.8152°E), 55 m, 16 March 2018, coll. Priya Prasad.

Etymology. The species epithet is a noun taken in apposition with reference to the Indian state, Odisha from where the holotype was collected.

Diagnosis. The species closely resembles to Theridion odoratum Zhu, 1998 by the genitalia morphology but can be distinguished by the laterally placed copulatory openings (closely placed, near the median axis in T. odoratum ); the copulatory duct wider at the distal region and narrowing proximally (uniform in T. odoratum ) and the ovoid spermatheca (globular in T. odoratum ) (cf. Figs 3–6 with figs 86B–C in Zhu, 1998); abdominal pattern, with a mid-dorsal white patch (absent in T. odoratum ) (cf. Fig. 1 with fig. 86A in Zhu, 1998). The abdominal pattern of the new species is more or less similar to Theridion petraeum L. Koch, 1872 and Theridion pinastri L. Koch 1872 , but can be easily distinguished from T. petraeum by the globular shape of the abdomen in new species (elongated in T. petraeum ) and from T. pinastri by the presence of yellowish dentate median band in new species (reddish band in T. pinastri ). Furthermore, these two species, T. petraeum and T. pinastri have different arrangement for coiling of copulatory duct. This new species have copulatory duct with a broader distal loop and narrow proximal region, while more complex and longer copulatory ducts, large atrium in T. pinastri and outwardly curved copulatory ducts in T. petraeum .

Description. Female (holotype). Total length: 2.55, carapace: 0.89 long, 0.77 wide; abdomen: 1.66 long, 1.75 wide. Eye measurements: AME 0.07, ALE 0.06, PME 0.08, PLE 0.07. Leg measurements: I 2.81 (0.58, 0.37, 0.88, 0.74, 0.24); II 2.69 (0.82, 0.31, 0.58, 0.63, 0.35); III 1.93 (0.56, 0.26, 0.36, 0.45, 0.30); IV 2.74 (0.77, 0.35, 0.55, 0.64, 0.43). Leg formula: 1423. Carapace yellow-brown with dark brown lateral margins ( Fig. 1 ). Sternum brownish with a lighter yellowish median region. Labium, maxillae and chelicera light brown ( Fig. 2 ). Legs yellowish with dark brown spots and annulations. Abdomen globular, brownish covered with pale white patches and a mid-dorsal broad white patch with wide serrated margins ( Fig. 1 ). Spinnerets yellowish-brown. Epigyne with lateral copulatory openings; copulatory ducts with a broader distal loop and narrow proximal region; spermathecae oval ( Figs 3–6 ).

MALE unknown.

Distribution. India (Odisha).

TABLE 1.

7. Theridion Nilgiris, Coonor – Simon, 1905 This species lacks the light nilgherinum (Tamil Nadu) dorsal band that characterizes

Simon, 1905 T. odisha sp.n. and related species of Theridion s. str.

8. Theridion Bhubaneshwar – odisha sp.n. (Odisha)

9. Theridion Nicobar Island – piligerum

Frauenfeld,

1867

10. Theridion Shalimar – sadani garden, Srinagar Monga & (Jammu and

Singh, 1989 Kashmir)

11. Theridion Jaunsar, Siri – subvittatum (Uttarakhand) Simon, 1889

12. Theridion Ahwa (Gujarat) – tikaderi

Patel, 1973

New species See diagnosis

Frauenfeld, 1867 T. piligerum is a nomen dubium even the description doesn’t indicate the sex of the specimen. The species is likely to be a synonym of one of the cosmopolitan theridiid species as described in ( Levi, 1967).

Monga & Singh, The description does not

1989 allow its confident placement in Theridion s. str., but it is not synonymous with T. odisha sp.n., as it has a different opisthosomal pattern with a dark midline.

Simon, 1889 As mentioned by Simon, 1889, T. subvittatum have an analogy with T. vittata . Levi (1956), have transferred T. vittata to the genus, Anelosimus Simon, 1891 . So, T. subvittatum should belong to the genus Anelosimus .

Patel, 1973 Based on the illustrations provided by ( Patel, 1973) the species is placed in the genus Nihonhimea Yoshida, 2016 (see discussion below)

13. Theridion Thrissur , China, Thailand, Thorell, 1890; T. zonulatum is a true zonulatum Ernakulam , Singapore, Zhu, 1998; Theridion with a striking and

Thorell, 1890 Trivandrum,Kol Indonesia Song, Zhu & Chen, having a different lam (Kerala) (Sumatra, 1999; Ehrler 2014; opisthosomal pattern, which Borneo) Sankaran et al., is not similar to T. odisha 2015 sp.n.

Figures

Figure 24. Distributional records of Theridion sp. in India.

Figures 1–6. Theridion odisha sp.n. 1, habitus, dorsal view. 2, same, ventral view. 3, epigyne, ventral view. 4, vulva, dorsal view. 5, epigyne, ventral view. 6, vulva, dorsal view. Scale bars 1–2, 1mm; 3–6, 0.2 mm