Elamena gracilis Borradaile, 1903

Devi, S. Suvarna, Mendoza, Jose C. E., Ravinesh, R., Idress Babu, K. K., Kumar, A. Biju & Ng, Peter K. L., 2019, On a collection of brachyuran crabs from Lakshadweep, Indian Ocean (Crustacea: Decapoda: Brachyura), Zootaxa 4613 (3), pp. 477-501 : 481

Elamena gracilis Borradaile, 1903

( Fig. 3 A–F)

Elamena gracilis Borradaile, 1903c: 684 , fig. 122; Gordon 1940: 71, figs. 1c, 6a, d, 7d; Dev Roy & Nandi 2005: 222, tab. 1.

Material examined. Lectotype (here designated): male (5.0 x 4.4 mm) ( CMZ I64238 ), on reef, Hulule, Male Atoll, Maldives, coll. J.S. Gardner, June 1900 . Paralectotypes: 1 ovigerous female (7.3 x 6.2 mm), same data as lectotype; 1 female (6.0 x 5.1 mm) ( CMZ I64236 ), on reef, Minicoy, Lakshadweep, coll. J.S. Gardner, June 1900 . Others: 1 female (6.0 x 5.3 mm) ( DABFUK), Kavaratti, 15 October 2014 .

Remarks. The species was first described based on material collected from Minicoy ( Lakshadweep) and Male Atoll ( Maldives) by Borradaile (1903c), with Gordon (1940) redescribing the species and figuring its gonopods for the first time. The species was subsequently listed by Dev Roy & Nandi (2005). Nevertheless, E. gracilis is not well known, so the types are figured here. Borradaile (1903c) and Gordon (1940) did not designate a holotype for E. gracilis so all the three specimens are syntypes. The male from Male Atoll is here selected as the lectotype of the species.

Gordon (1940) compared E. gracilis with the similar E. sindensis Alcock, 1900 , and E. mathoei (Desmarest, 1823) from the Indian Ocean and showed they were distinct in several carapace, ambulatory leg and G1 characters (see also Ng & Chuang 1996). The carapace shape varies slightly, with the lectotype male proportionately longer and the anterolateral margins slightly more concave ( Fig. 3A ) than in other specimens; the female carapace may also be proportionally wider ( Fig. 3B, C ).

Figures

FIGURE 3. Elamena gracilis (A–F). A, D–F, lectotype, male, 5.0 x 4.4 mm (CMZ I64238), Male Atoll, Maldives; B, paralectotype, female, 6.0 x 5.1 mm) (CMZ I64236), on reef, Minicoy; C, ovig. female, 7.3 x 6.2 mm, same data as lectotype.A–C, dorsal habitus; D, left third maxilliped, external view; E, pleon and pleotelson, ventral view; F, left G1, abdominal (external) view. Scale bar: 0.5 mm.