Arctosa dhikala Sankaran & Caleb
Creators: name: Sankaran, Pradeep M.
name: Caleb, John T. D.
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Lycosidae
Arctosa
Arctosa dhikala

description: Arctosa dhikala comb. et nom. nov.
Figs 1–2
Trochosa himalayensis Tikader & Malhotra, 1980: 437, figs 349–353 (♂ ♀).
Etymology. The specific epithet ‘ dhikala ’ is a noun in apposition derived from the name of the type locality of T. himalayensis.
Type material. Holotype ♀ from INDIA: Uttarakhand: Pauri: Jim Corbet National Park (formerly in Uttar Pradesh): Dhikala (29°36’N, 78°48’E; 508 m alt.), leg. Asket Singh, 29 November 1971, repository NZC-ZSI, Kolkata (4660/18), examined. Paratypes 1 ♂, 3 ♀♀ with same data as holotype except 4661/18, examined.
Additional material examined. 1 ♂ (labelled as allotype) with same data as holotype (NZC-ZSI, Kolkata 4662/18).
Diagnosis. Males of A. dhikala are closely related to the males of Arctosa indica Tikader & Malhotra, 1980 as both share a median apophysis with narrow distal part, but can be distinguished from the latter species by the median apophysis with a pointed apex and without lateral process (vs. truncated and with lateral process in A. indica; compare Fig. 2B–C with Sankaran et al. 2021: fig. 6B–C). Females are most similar to the females of Arctosa khudiensis (Sinha, 1951) as both share a large median epigynal septum and oval spermathecae with short stalk, but can be distinguished from the latter species by the squarish distal part of epigynal median septum (vs. triangular in A. khudiensis), and the slender stalk of spermathecae (vs. stout in A. khudiensis; compare Fig. 2D, F with Sankaran et al. 2021: fig. 8A, C).
Supplementary description. Male (4662/18; Fig. 1A). Fovea vertical, dark. Cheliceral promargin with two teeth, retromargin with three. Body length 5.34. Carapace 2.98 long, 2.07 wide. Opisthosoma 2.36 long, 1.38 wide. Eye diameters and interdistances: ALE 0.08. AME 0.10. PLE 0.20. PME 0.23; ALE–AME 0.02. AME–AME 0.07. PLE–PLE 0.38. PME–PLE 0.17. PME–PME 0.14. Chelicerae 0.93 long. Clypeus height at ALE 0.06, at AME 0.05. Measurements of palp and legs. Palp 2.47 [0.82, 0.48, 0.36, 0.81], leg III ---- [1.48, 0.70, 0.91, 1.29, ----]. Palp as in Fig. 2A–C.
Female (holotype, 4660/18; Fig. 1B). Same as male except by the following: body length 6.87. Carapace 3.43 long, 2.30 wide. Opisthosoma 3.44 long, 2.03 wide. Eye diameters and interdistances: ALE 0.11. AME 0.13. PLE 0.22. PME 0.30; ALE–AME 0.03. AME–AME 0.08. PLE–PLE 0.27. PME–PLE 0.55. PME–PME 0.16. Chelicerae 1.48 long. Clypeus height at ALE 0.10, at AME 0.09. Measurements of palp and legs. Palp 3.65 [1.12, 0.67, 0.90, 0.96], I 8.19 [2.34, 1.25, 1.71, 1.84, 1.05], II 7.46 [2.10, 1.13, 1.45, 1.73, 1.05], III 6.91 [1.93, 1.00, 1.24, 1.78, 0.96], IV (right) 10.01 [2.23, 1.50, 2.69, 2.37, 1.22]. Leg formula: 4123. Genitalia (Fig. 2D): epigynal plate almost circular, lightly sclerotized. Median septum with narrow proximal and squarish distal parts. Copulatory openings small, lying posterolaterally to median septum.
Female (paratype, Fig. 2E–F). epigynal plate almost circular, lightly sclerotized (Fig. 2E). Median septum with narrow proximal and squarish distal parts (Fig. 2E). Copulatory openings small, lying posterolaterally to median septum (Fig. 2E). Spermathecal stalks short, narrow (Fig. 2F). Spermathecae oval (Fig. 2F).
Measurements of paratypes. Male: body length 5.17. Carapace 2.84 long, 2.07 wide. Opisthosoma 2.33 long, 1.43 wide. Female 1 (Fig. 1C): body length 6.67. Carapace 3.62 long, 2.61 wide. Opisthosoma 3.05 long, 1.92 wide. Female 2: body length 5.02. Carapace 2.34 long, 1.83 wide. Opisthosoma 2.68 long, 1.84 wide. Female 3: body length 4.96. Carapace 2.59 long, 1.90 wide. Opisthosoma 2.37 long, 1.53 wide.
Notes. Tikader & Malhotra (1980) described this species based on male and female specimens collected from Uttarakhand. Detailed examination of the types of T. himalayensis shows that it has diagnostic features of Arctosa, including terminal apophysis with two parts, epigyne with conspicuous atrium divided by median septum, and similar structural organisation of internal duct system as seen in Arctosa cinerea (Fabricius, 1777), the type species of the genus (compare Fig. 2B–F with Buchar et al. 2006: figs 25–26; Wang et al. 2012: fig. 12A–E). Based on these observations, we propose to transfer T. himalayensis to Arctosa.
By transferring T. himalayensis to Arctosa, it becomes a secondary junior homonym in Arctosa, as the name is preoccupied with Arctosa himalayensis Tikader & Malhotra, 1980 (Tikader & Malhotra 1980; World Spider Catalog 2023). According to ICZN Article 60.3 (ICZN 1999), we propose a replacement name.
The ZSI collection has three glass tubes for this species. A tube labelled as ‘holotype’ (4660/18) contains one female specimen in good condition, with intact genitalia. A second tube labelled as ‘paratype’ (4661/18) contains three female and one male specimens in good condition (but the label mentions only ‘three females’). The genitalia of one of the females was found to be dissected and kept in a small glass vial in the same tube. A third tube labelled as ‘allotype’ (4662/18) contains one male specimen in fairly good condition, with broken legs. Its right palp was found to be removed and kept in a small glass vial in the same tube. In the original description, a single registration number was assigned for the holotype, paratype and allotype (Tikader & Malhotra 1980). However, the labels in the type vials mention separate registration numbers for the holotype, paratype and allotype.
Distribution. India (Uttarakhand, Tikader & Malhotra 1980).
description: Published as part of Sankaran, Pradeep M. & Caleb, John T. D., 2023, Notes on Indian wolf spiders: III. Genera Acantholycosa Dahl, 1908, Evippomma Roewer, 1959, Hippasosa Roewer, 1960 and Trochosa C. L. Koch, 1847 (Araneae: Lycosidae), pp. 533-552 in Zootaxa 5369 (4) on pages 534-537, DOI: 10.11646/zootaxa.5369.4.4, http://zenodo.org/record/10145893