Carrhotus silanthi Caleb, 2020

Satkunanathan, Abira & Benjamin, Suresh P., 2022, Phylogenetic placement of Carrhotus Thorell, 1891 with three new species from Sri Lanka (Araneae: Salticidae), European Journal of Taxonomy 817 (1), pp. 78-110 : 95-98

Carrhotus silanthi Caleb, 2020

Figs 10A–F , 11A–H , 12A–D , 17

Carrhotus silanthi Caleb in Caleb et al., 2020: 58, Figs 33–56.

Diagnosis

Males of C. silanthi can be separated from other congeners by having the RTA markedly hook-shaped, slanted ventrally, and the distally pointed acuminate embolus ( Fig. 12A–B ). Females can be readily separated from those of C. albosetosus sp. nov. by the prominent ML and the position of the opening of the accessory glands on the internal spermathecal walls, close to the base of the copulatory ducts ( Figs 11G , 12C–D ).

Type material

Carrhotus silanthi Caleb in Caleb et al., 2020: 58, Figs 33–56 (male holotype and female paratype from Madras Christian College, Tambaram, Chennai, India, deposited in NZC-ZSI, Kolkata ( NZC-ZSI 6939/18, NZC-ZSI 6940/18)). Not examined.

Material examined

SRI LANKA – Uva Province • 1 ♂, 1 ♀; Monaragala District, Nilgala FR; 07°11′08″ N, 81°24′24″ E; 122 m a.s.l; 12 Jul. 2017; N. Athukorala and I.S. IIeperuma Arachchi leg.; beating; NIFS_SAL_1042 , SAL_1043 . – North Central Province • 1 ♂, 1 ♀; Anuradhapura District, Mihintale Sanctuary ; 08°20′59″ N, 80°30′20″ E; 119 m a.s.l; 14 Jun. 2016; N. Athukorala et al. leg.; beating; NIFS_SAL_824 , SAL_825 • 1 ♂; Allepothana, Kok-ebe FR; 08°26′58″ N, 80°46′39′ E; 88 m a.s.l; 24 Apr. 2017; N. Kanesharatnam leg.; beating; NIFS_SAL_1032 . – Northern Province • 2 ♂♂, 1 ♀; Mannar District, Giant’s Tank Sanctuary ( Site 1 ); 27 m a.s.l; 4 Apr. 2018; S.P. Benjamin et al. leg.; beating; NIFS_ SAL_1137 to SAL_1139 • 1 ♀; same collection data as for preceding; NIFS_SAL_1162 . – Southern

Province • 1 ♂; Hambantota District , Ussangoda NP; 06°05′43″ N, 80°59′15″ E; 22 Nov. 2017; S.P. Benjamin et al. leg.; beating; NIFS_SAL_1116 .

Description (based on material from Sri Lanka)

Male

MEASUREMENTS. TL 4.8, PL 2.16, PW at PLEs 1.786,AL 2.19, AW 1.44. Eye field: diameter of AME 0.44; ALE 0.26; PME 0.12; PLE 0.24; PME–PME 1.68; PLE–PLE 1.44; ALE–PME 0.36; ALE–PLE 0.6. Leg I: Tr 1.2, Fm 0.82, Pt 0.78, Tb 1.22, Mt 0.62; Leg II: Tr 1.48, Fm 0.42, Pt 0.62, Tb 1.02, Mt 0.56; Leg III: Tr 1, Fm 0.7, Pt 0.72, Tb 1.06, Mt 0.5; Leg IV: Tr 0.84, Fm 0.6, Pt 1, Tb 1.02, Mt 0.62.

COLOR AND BODY. In live spiders, both sexes look similar in general body colour pattern and are clothed with iridescent hairs. Colour varies from metallic sheen to bronze-green as shown in Fig. 10A–F . Carapace: prosoma reddish-brown covered with iridescent hairs providing a metallic sheen; lateral margins of carapace lined by broad patches of white hairs; posterior region black. Hairs sparse. Sternum oval, brownish; labium and maxillae dark brown, with paler outer margins. Clypeal region brownish; eyes surrounded by yellowish orbital setae. Chelicerae dark brown with curved outer margins and excavated inner margins: two promarginal and one retromarginal teeth. Abdomen ovoid, densely covered with rusty brown hairs; anterior margin covered by white scales; pattern present on black background with pair of white spots anteriorly and pairs of transverse stripes following posteriorly ( Fig. 11A–B ). Middorsum covered with scales of metallic sheen; venter yellowish, with a broad dark brown median region. Spinnerets brownish, covered with a patch of white hairs dorsally. Leg I robust; femora I-IV dark brown dorsally; patellae and tibiae dark brown; tarsi and metatarsi of all legs dark brown.

PALP. Dark brown; embolus short and thick with a blunt tip and embolus tip directed in clockwise path, its base separated from tegulum; bulbus with PLP; RTA markedly hook-shaped bent ventrally and angle between RTA and tibia about 45º ( Figs 11E–F , 12A–B ).

Female

MEASUREMENTS. TL 5.5, PL 2.04, PW at PLEs 1.95, AL 2.64, AW 2.16. Eye field: diameter of AME 0.48; ALE 0.26; PME 0.12; PLE 0.24; PME–PME 1.5; PLE–PLE 1.46; ALE–PME 0.44; ALE–PLE 0.78. Leg I: Tr 1, Fm 0.92, Pt 0.94, Tb 0.56, Mt 0.38; Leg II: Tr 1.2, Fm 0.78, Pt 1.1, Tb 0.7, Mt 0.46; Leg III: Tr 1.3, Fm 0.8, Pt 1.02, Tb 0.6, Mt 0.42; Leg IV: Tr 1, Fm 0.74, Pt 1.1, Tb 0.4, Mt 0.32.

COLOR AND BODY. Colouration pattern as in male, but differs as follows: AMEs surrounded by yellow orbital setae; clypeus covered with white hairs; carapace with white hairs making an arc behind PLEs. Abdomen ovoid, densely covered with rusty brown hairs; anterior margin covered by white scales; pattern present on black background with pair of white spots anteriorly and pairs of transverse stripes following posteriorly ( Fig. 11C–D ). Mid-dorsum covered with scales of metallic sheen; venter yellowish, with a broad dark brown median region. Spinnerets brownish, covered with a patch of white hairs dorsally. Legs with white border on distal margin of femur I–IV; other segments covered with sparse white hairs and black annulations alternatively.

EPIGYNUM. Epigyne with a pair of simple copulatory openings placed in small oval, yellowish depressions; copulatory ducts short, diverge to join stomach-shaped spermathecae.Accessory glands open on internal spermathecal walls close to base of copulatory ducts ( Fig. 12C–D ).

Intraspecific variation

The palpal conformation of NIFS_SAL_1116 closely resembles that of C. silanthi . However, it differs by having the PLP shorter and less rounded ( Fig. 11F ) vs oval-shaped PLP in C. silanthi ( Fig. 11E ), and a short, cone-shaped embolus ( Fig. 11F ) in NIFS_SAL_1116 vs a thinner embolus in C. silanthi ( Fig. 11E ).

Distribution and habitat

This species occurs in the lowland secondary rainforests of the dry and wet zones of Sri Lanka including the Ussangoda dry zone National Park in Hambantota District in the Southern Province ( Fig. 17 ). Specimens were collected by beating vegetation up to a height of 1– 2 m.

Figures

Fig 10. Photographs of live Carrhotus silanthi Caleb, 2020, males. A–C. From Giants Tank Sanctuary. D–F. From Ussangoda.

Fig 12. Carrhotus silanthi Caleb, 2020.A–B. Palp.A. Ventral view.B. Retrolateral view.C–D. Epigynum. C. Ventral view. D. Dorsal view. Abbreviations: AG = accessory gland; E = embolus; FD = fertilization duct; RTA = retrolateral tibial apophysis; S = spermatheca; TE = tegulum. Scale bars: A–B = 0.2 mm; C–D = 0.1 mm.

Fig 17. Distribution of Carrhotus spp. of Sri Lanka.

Fig. 11. Carrhotus silanthi Caleb, 2020. A–B. Male habitus. A. Dorsal view. B. Ventral view. C–D. Female habitus. C. Dorsal view. D. Ventral view. E–H. Palp. E–F. Ventral view; the arrows showing the embolus tip directed in clockwise (11E) or directed in apical (11F). G–H. Retrolateral view. Abbreviations: PLP = posterior lateral protrusion; RTA = retrolateral tibial apophysis; TE = tegulum. Scale bars: A–D = 2 mm; E–H = 0.2 mm.