Diogenes jousseaumei ( Bouvier, 1897 )

Rahayu, Dwi Listyo, 2022, Hermit crabs of Singapore (Crustacea: Decapoda: Anomura: Diogenidae, Paguridae), with description of two new species, Raffles Bulletin of Zoology 70, pp. 329-363 : 340

Diogenes jousseaumei ( Bouvier, 1897)

( Figs. 5G–I , 7E )

Troglopagurus jousseaumei Bouvier, 1897: 231 , fig. 6 (type locality: Red Sea); Nobili, 1906a: 79, 81 (key); 1906b: 120.

Diogenes senex ‒ Lanchester, 1902: 366 (Not Diogenes senex Heller, 1865 ).

Diogenes jousseaumei ‒ Forest, 1952: 8, fig. 15; Morgan, 1987b: 179; Morgan & Forest, 1991: 677, fig. 11; McLaughlin, 2005: 609, figs. 1d–f, 2.

Diogenes setocristatus Morgan & Forest, 1991: 665 , figs. 7, 8 (type locality: Southwest Peel Island , Southwest Queensland, Australia).

Diogenes stenops Morgan & Forest, 1991: 671 , figs. 9, 10 (type locality: Cape Bowling Green, Queensland, Australia); Rahayu, 1996: 349; McLaughlin & Clark, 1997: 43, figs. 7a, 9g, 13b; Rahayu & Hortle, 2002: 617.

Not Troglopagurus jousseaumeii – Alcock, 1905b: 75, pl. 5, fig. 6 (in part). = Diogenes manaarensis ( Henderson, 1893) , and D. persicus ( Nobili, 1905) (misspelling of jouseaumei).

Not Troglopagurus jousseaumei – Thompson, 1943: 416. = Diogenes persicus ( Nobili, 1905) .

Material examined. 1 ovigerous female, 5.8 mm ( ZRC 2021.0128 ), st. 4815TB1, Along Sentosa, beside Rasa Sentosa, 1°15.232′N 103°48.475′E – 1°14.910′N 103°48.825′E, 20.1‒ 17.7 m, sand, 11 January 2013; 1 male , 3.3 mm ( MZB Cru 5204), st. TB 98, Eastern Bunkering A, 1°18.938′N 104°05.312′E, 33.6‒ 30.2 m, broken shell, silt, 28 May 2013; 1 male , 2.2 mm ( ZRC 2021.0129 ), st. 5416TB2, Outside Tanjung Rhu, 01°23.500′N 103°59.500′E, 22.7‒23.7 m, 14 January 2013 .

Colour. Shield cream mottled with greenish brown; ocular peduncles creamy white with dark brown longitudinal stripe dorsally, cornea silvery black; chelipeds cream with brown streak on palm, carpus, and merus with brown band medially. P2 and P3 creamy white, with brown band proximally on dactyls, medially and proximally on propodi, medially on carpi and meri ( Fig. 7E ).

Distribution. From the Red Sea to Thailand, Singapore, Malaysia, Indonesia, and Australia (Northern Territory, Queensland, and Western Australia); subtidal, 10–150 m, on sandy, mud substrate.

Remarks. The colour in life of the specimens in this study agrees well with Haig & Ball (1988) for the specimens from Arafura. Rahayu & Hortle (2002) gave the description of the colour in life of this species as D. stenops . Among the species of Diogenes in the Troglopagurus group, D. jousseaumei is recognisable by the long and slender ocular peduncle, which is as long as or slightly longer than the shield, and the presence of a longitudinal stripe on the dorsal surface, which persists in preserved specimens ( Figs. 5G , 7E ). This species was already recorded from Singapore waters as D. stenops by Rahayu (1996).

Figures

Fig. 5. A–C, Diogenes jubatus (Nobili, 1903), male, 5.1 mm (ZRC 2021.0114); D–F, Diogenes platyops Rahayu & Forest, 1995, male, 4.9 mm (ZRC 2021.0118); G–I, Diogenes jousseaumei (Bouvier, 1897), ovigerous female, 5.8 mm (ZRC 2021.0128). A, D, G, shield and cephalic appendages; B, E, H, anterior lobe of sternite of third pereopods; C, F, I, telson. Scale = 1 mm.

Fig. 7. A, B, Diogenes jubatus (Nobili, 1903); A, ovigerous female, not collected, Johor Strait, 21 October 2012; B, male, 5.1 mm (ZRC 2021.0114); C, D,Diogenes platyops Rahayu & Forest, 1995; C, male (not collected), st. TB29, Singapore Strait,01°13.036′N 103°52.820′E, 22 May 2013; D, ovigerous female, 3.5 mm (ZRC 2021.0125); E, Diogenes jousseaumei (Bouvier, 1897), male, 2.2 mm (ZRC 2021.0129).