Habrocestum swaminathan Jose & Caleb & Sudhikumar 2024, sp. nov.
Creators: name: Jose, Athira
name: Caleb, John T. D.
name: Sudhikumar, Ambalaparambil Vasu
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Salticidae
Habrocestum
Habrocestum swaminathan

description: Habrocestum swaminathan sp. nov.
Figs 1G–H, 4A–H, 5A–D, 7A–D
Type material. Holotype: ♂ (CATE 10321853a) from INDIA: Kerala: Palakkad: Silent Valley National Park (11°5′40″N, 76°27′3″E, 980 m alt.), 12 March 2023, A. Jose coll., from litter, by hand. Paratype: 1♀ (CATE 10321853b), same data as for holotype.
Etymology. The specific epithet is a patronym in honor of the late Dr. M. S. Swaminathan, the father of Indian green revolution, for his efforts, passion and contributions to the society. The name is treated as a noun in apposition.
Diagnosis. Male of Habrocestum swaminathan sp. nov. is mostly similar to H. shendurneyense Asima, Caleb, Babu & Prasad, 2022, with the shared absence of a proximal lobe of tegulum. However, the new species can be easily distinguished by the absence of a retrobasal cymbial extension (vs. present in H. shendurneyense), comparatively long embolus (vs. short in H. shendurneyense), and long RTA with a pointed, slightly curved tip (vs. small RTA with a broad, blunt tip in H. shendurneyense) (Figs 5A–B, 7A–B vs. figs 14–15 in Asima et al. 2022). Additionally, the palp shares similarities with that of H. gibbosum Wesołowska & van Harten, 2007, particularly in the shape of the RTA and embolus, but can be differentiated by the absence of proximal lobe of tegulum (vs. present in H. gibbosum), relatively shorter embolus with broad base (vs. narrow, long, ribbon-like in H. gibbosum), ventral margin of RTA straight in retrolateral view (vs. curved in H. gibbosum) (Figs 5A–B, 7A–B vs. figs 58, 59 in Wesołowska & van Harten 2007). Females are comparable to H. hantaneense Kanesharatnam & Benjamin, 2016 in the general appearance, but differs by the medially thin epigyne pocket with triangular shallow notch (vs. thin epigynal pocket with notch not triangular in H. hantaneense), the proximal end of spermatheca slender and inwardly folded (vs. broad, not folded in H. hantaneense), closely placed median window (vs. distally placed in H. hantaneense), and the copulatory openings placed along the medial region (vs. mid-lateral region in H. hantaneense) (Figs 5C–D, 7C–D vs. figs 5E–F, 6C–D in Kanesharatnam & Benjamin 2016).
Description. Male (Holotype, CATE 10321853a) (Figs 1G, 4A–D, 5A–B & 7A–B). Measurements: body length 3.45; carapace 1.89 long, 1.46 wide, 1.09 height; abdomen 1.56 long, 1.29 wide. Eye sizes and ocular distance: AME 0.43, ALE 0.27, PME 0.07, PLE 0.25; AME–AME 0.04, AME–ALE 0.04, PME–PME 1.15, ALE–ALE 1.13, PME–PLE 0.16, PLE–PLE 1.08, ALE–PME 0.34, ALE–PLE 0.57; Length of chelicerae 0.53. Clypeus height at AMEs 0.13. Length of pedipalp and legs: pedipalp 1.74 (0.59, 0.37, 0.20, 0.58), I 3.78 (1.05, 0.53, 1.13, 0.65, 0.42), II 2.78 (0.82, 0.53, 0.65, 0.49, 0.29), III 2.97 (0.97, 0.50, 0.62, 0.65, 0.23), IV 2.99 (0.88, 0.46, 0.60, 0.67, 0.33). Leg formula: 1342. Spination of legs: femur I do 1, II pld 1, III pld 2 do 2, IV do 1; patella I–II 0, III–IV rl 1; tibia I plv 4 rlv 3, II pl 2 plv 2 rlv 3, III pld 2 rld 2, IV pld 2 rld 3; metatarsus I plv 2 rlv 2, II plv 4 rlv 2, III–IV pl 2 pld 2 plv 2 rl 1 rld 2 rlv 2; tarsus I–IV 0. Colouration (in alcohol): carapace orange-brown, with sparse black hairs posteriorly; anterolaterally a distinct white stripe extends along lateral midline to posterior dorsum; a faint patch of white hairs present below fovea; eye field black, adorned with pale yellow hairs, intermixed with long black vertical hairs that fringe above AER in lateral view (Fig. 4B); outer margin defined by flame orange hairs, extends posteriorly to about 3/4th of carapace margin, below white patch; clypeus colour same as carapace, sparsely covered with black long hairs; chelicerae chestnut brown; endites and sternum pale brown. Legs creamy white uniformly. Abdomen brown, hairy, marked with a faint crescent shape frontally and chevron patterns posteriorly, venter creamy white. Carapace longer than abdomen, nearly U-shaped, broadest behind the PMEs, slopes gently toward the front, rear truncated with abrupt posterior slope; eye field short, raised. Fovea small, indistinct. Chelicerae with two closely spaced teeth on promargin and single bicuspid tooth on retromargin, with one ramous reduced and blunt; endites with fewer scopulae, absent on labium. Abdomen oval, narrower than the prosoma; spinnerets elongated. Pedipalp (Figs 5A–B, 7A–B): tibia and cymbium tan brown, other legs creamy white; patella dorsum, cymbium and tibia disto-prolaterally covered with long white hairs. Cymbium long, elongated apically. Tegulum oval with a medial tegular cleft, proximal lobe of tegulum absent; tegular ledge present, covers half of tegulum and extends to embolic base. Embolus arises from 9 o'clock position and is directed at 11 o'clock position; RTA small, stout, broad at base, with a beak-like, curved, pointed tip.
Female (Paratype) (Figs 1H, 4E–H, 5C–D & 7C–D). Measurements: body length 4.20; carapace 1.92 long, 1.44 wide, 0.98 height; abdomen 2.28 long, 1.74 wide. Eye sizes and ocular distance: AME 0.44, ALE 0.26, PME 0.08, PLE 0.17; AME – AME 0.02, AME – ALE 0.03, ALE – ALE 1.10, PME – PME 1.07, PME – PLE 0.19, PLE – PLE 1.13, ALE – PME 0.26, ALE – PLE 0.54. Length of chelicerae 0.48. Clypeus height at AMEs 0.09. Length of palp and legs: palp 1.46 (0.55, 0.22, 0.27, 0.42); I 3.23 (1.03, 0.57, 0.78, 0.51, 0.34), II 2.46 (0.82, 0.43, 0.54, 0.41, 0.26), III 3.27 (1.18, 0.50, 0.67, 0.65, 0.27), IV 3.3 (1.1, 0.42, 0.67, 0.75, 0.36). Leg formula 4312. Spination of legs: femur I pld 3, II pld 2 do 2, III do 3 rld 1, IV do 3; patella I–III 0, IV rl 1; tibia I plv 4 rlv 3, II pl 1 plv 3 rlv 3, III pl 2 plv1 rl 2, IV rl 2; metatarsus I plv 2 rlv 2, II plv 4 rlv 2, III–IV pl 1 pld 2 plv 2 rl 1 rld 2 rlv 2; tarsus I–IV 0. Colouration (in alcohol): body form and colour same as in male, except, carapace and clypeus brown, eye field black with a distinct red patch above AMEs. 3/4th of carapace clothed with pale yellow hairs. Abdomen venter mottled with brown patches. Palp pale yellow. Epigyne with a pair of postero-lateral pockets. Windows large, copulatory openings situated medially (Figs 5C–D, 7C–D). Tubular accessory glands seen emerging from below spermathecae and move laterally, which are apparent in ventral view (Figs 5C, 7C). Copulatory ducts short. Spermathecae with moderately sclerotized posterior portion, anterior portion tube-like with thick walls, bent like swans facing each other. Fertilization ducts narrow, directed antero-laterally (Figs 5D, 7D).
Natural history. Habrocestum swaminathan sp. nov. was spotted actively moving on the forest floor which had minimal litter depth, near a stream in the closed evergreen forest. Multiple sightings of this species were recorded during the observation period, indicating its association with the habitat.
Distribution. Known only from the type locality.
description: Published as part of Jose, Athira, Caleb, John T. D. & Sudhikumar, Ambalaparambil Vasu, 2024, On three species of the genus Habrocestum Simon, 1876 (Araneae: Salticidae: Hasariini) from India, pp. 212-224 in Zootaxa 5448 (2) on pages 217-220, DOI: 10.11646/zootaxa.5448.2.3, http://zenodo.org/record/11231400