Chhapgarus intermedius Ng & Trivedi & Bhat 2022, comb. nov.
Creators: name: Ng, Ngan Kee
name: Trivedi, Jigneshkumar
name: Bhat, Mithila
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Decapoda
Varunidae
Chhapgarus
Chhapgarus intermedius

description: Chhapgarus intermedius (Chhapgar, 1955) comb. nov.
(Figs. 1–6)
Pseudograpsus intermedius Chhapgar, 1955: 257.— Chhapgar 1957: 519.— Hashmi 1964: 452.— Sethuramalingam & Khan 1991: 89.— Selvakumar & Khan 1993: 337.— Tirmizi & Ghani 1996: 170, fig. 65.— Chakraborty et al, 2002: 1392.— Khan et al. 2005: 1319.— Dev Roy & Nandi 2007: 180.— Ravichandran & Kannupandi 2007: 333 (in list).— Haragi et al. 2010: 10 (in list).— Dineshbabu et al, 2011: 23 (in list).— Pawar 2012: 90 (in list).— Trivedi et al. 2018: 75 (in list).
Holotype: ZSI C3-363/1, male (CW 10.7 mm, CL 9.0 mm), Mumbai, Maharastra State, India, 17 March 1953, coll. B. F. Chhapgar.
Other material examined: LFSC.ZRC-154, 8 males (CW 5.8–11.1 mm, CL 5.4–10.0 mm), 6 females (CW 6.1­ – 8.6 mm, CL 5.5–7.6 mm), Chapora Estuary (1­ 5°37′95″N, 73°45′76″E), Goa state, India, 7 September 201­ 6, coll. M. Bhat; RMNH D-30417, 1 male (CW 11.3 mm, CL 10.4 mm), 1 female (CW 8.6 mm, CL 7.6 mm), Kali River estuary, Karnataka state, India, 1974–1975, coll. U. S. Kakati.
Description. Carapace squarish, slightly broader than long; dorsal surface covered with short-brown setae, regions not well defined, convex. Frontal margin slightly convex, slightly bilobed (Figs. 1A, 2A, 4A, 5A, 6A). Anterolateral margin subcristate with three teeth, including orbital tooth, external orbital tooth most distinct, very broad; second tooth smaller in size, third tooth smallest. Posterolateral margins not sharply demarcated from anterolateral margin, almost straight, distinctly converging. Orbits small, eyes completely filling orbit (Figs. 1A, 2A, 4A, 5A, 6A).
Third maxilliped with foliaceous merus, broader than long; anterolateral angle produced, auriculiform; distal margin distinctly bilobed, outer lobe larger, base with small median cleft. Ischium longer than broad, sulcus not discernible. Small, distinct rhomboidal gape formed when closed. Exopod with obtuse, blunt inner subdistal angle, flagellum prominent, longer than width of merus (Fig. 2D). Epistome broad, flat, posterior margin entire.
Male chelipeds equal to subequal, inner surfaces glabrous; merus without spines, dorsal surface highly setose; carpus without spines or teeth; outer surface of fingers with tufts of long, soft setae. Fingers slightly shorter than palm; dactylus with one large tooth medially followed by small teeth, pollex cutting edge with small teeth, one large tooth present proximally, single prominent ridge present on pollex, finger tips recurved, sharp, hooved (Figs. 1A, B, 2B, 4B). Female chelae slender than those of male, outer surface covered with short setae, a prominent ridge running parallel to the ventral margin (Figs. 2C, 5B).
Ambulatory legs with second pair longest. Merus of all ambulatory legs with long, soft setae; anterior margin with blunt subdistal tooth; outer surface of carpus with short setae, anterior and posterior margins of propodus with short setae (Figs. 1A, C, 3F–I, 4A, C, 5A, C, 6A, B).
Male pleon narrowly triangular with all segments freely moveable (six somites plus telson), lateral margins highly setose (Figs. 1C, 2E, 4C, 6B); female pleon similar, very broad (Figs. 3A, 5B). G1 stout, gently curving outwards, terminal lobe elongate, slightly curved (Figs. 3B–D). G2 short, small (Fig. 3E). Female vulvae operculate, circular (Fig. 3J).
Distribution. The species is so far reported from Pakistan (Tirmizi & Ghani 1996) and India (Trivedi et al. 2018). In India, the species is reported from Maharashtra (Chhapgar 1955, 1957; Pawar 2012), Karnataka (Haragi et al. 2010; Dineshbabu et al. 2011), and Tamil Nadu (Sethuramalingam & Khan 1991; Selvakumar & Khan 1993; Khan et al. 2005; Dev Roy & Nandi 2007; Ravichandran & Kannupandi 2007).
Ecology. Chhapgarus intermedius comb. nov. inhabits the mid-intertidal zone in mangrove habitats. Individuals of the species are mostly found under dead logs or rock boulders, and sometimes also in burrows.
Coloration. The carapace of fresh specimens is chestnut brown with short black setae. The cheliped and ambulatory legs are light brown. Sternum and abdomen are also light brown.
Remarks. Chhapgarus intermedius (Chhapgar, 1955) comb. nov. was described on the basis of 14 specimens (ten males; two females and two ovigerous females) collected from Mumbai (Bombay), Maharashtra State, India (Chhapgar 1955). The holotype male, which was deposited in Zoological Survey of India, Kolkata has been examined in the present study but the rest of the specimens (paratype) examined by Chhapgar (1955) are not traceable. Fresh specimens examined in the present study show agreement with the illustrations and original descriptions given by Chhapgar (1955).
description: Published as part of Ng, Ngan Kee, Trivedi, Jigneshkumar & Bhat, Mithila, 2022, Redescription of Pseudograpsus intermedius Chhapgar, 1955 (Decapoda, Brachyura, Varunidae) from India, pp. 127-138 in Zootaxa 5209 (1) on page 131, DOI: 10.11646/zootaxa.5209.1.7, http://zenodo.org/record/7322612