Eriphia gonagra ( Fabricius, 1781 )

Koh, S. K. & Ng, Peter K. L., 2008, A Revision Of The Shore Crabs Of The Genus Eriphia (Crustacea: Brachyura: Eriphiidae), Raffles Bulletin of Zoology 56 (2), pp. 327-355 : 330-332

Eriphia gonagra ( Fabricius, 1781)

( Figs. 2 , 3D–F )

Cancer gonagra Fabricius, 1781: 505 ; Herbst, 1788: 238.

Eriphia gonagra – H. Milne Edwards, 1834: 426; Dana, 1852b: 250; Stimpson, 1860: 217; Herklots, 1861: 125; Heller, 1865: 24; Stimpson, 1871: 10; Von Martens, 1872: 92; Miers, 1886: 162, 163; Ortmann, 1893: 480; Rathbun, 1897b: 21; Rathbun, 1898a: 276; Rathbun, 1898b: 590; Rathbun, 1900: 141; Rankin, 1900: 527; Verril, 1908: 362; Hay & Shore, 1918: 439, Pl. 35 Fig. 6 ; Boone, 1930: 144, Pl. 47 Fig. B; Rathbun, 1930: 545, Text–Fig. 83, pl. 222; Rathbun, 1933: 75; Rathbun, 1936: 386; Finnegan, 1931: 646; Lunz, 1937: 25; Holthuis, 1959: 210; Williams, 1965: 182, Figs. 164A–C; Coelho & Ramos, 1972: 192; Gomes-Corrêa, 1972: 7; Felder, 1973: 64, Fig. 5 ; Powers, 1977: 90; Garth, 1978: 327; Rodriguez, 1980: 370, Pl. 54; Lemaitre, 1981: 251; Williams, 1984: 419; Abele & Kim, 1986: 652; De Melo, 1996: 346; De Melo, 1998: 482; De Melo, 1999: 458, Fig. 45; Boschi, 2000: 80; Nizinski, 2003: 137; Ng et al., 2008: 63.

Eriphia armata Dana, 1852a: 83 ; Dana, 1852b: 248; Dana, 1855, Pl. 14 Fig. 6a–d ; Miers, 1886: 162.

Eriphia laevimana var. smithi i – Cano, 1838: 210 (part) (not MacLeay, 1838).

Material examined. – Lectotype: 1 dried male (11.7 × 16.2 mm) ( ZMUC Cru 37), Jamaica, Banks Collection. Others: JAMAICA: 2 dried males ( MMUS – C 1989–1990 ). ST. THOMAS ISLAND: 1 male, 1 female ( ZMUC), Fabricius Collection. BRAZIL: 1 male (18.7 × 26.0 mm), 1 female (27.1 × 41.3 mm) ( NHM 1887.23 ), Pernanamburo, coll. H. N. Ridley; 1 male (24.6 × 36.9 mm), 1 female (25.2 × 28.7 mm) ( USNM 40572 ), Pernanambuco , coll. Hartt Exploring Expedition, 1875–1877; 1 male ( ZMUC), Rio de Janeiro, Fabricius Collection. CUBA: 1 dried male, 1 female ( MMUS – C 1987–1988 ). NORTH AMERICA: 1 male (21.1 × 29.5 mm), 1 female (11.0 × 15.8 mm) ( USNM 57127 ), Florida , Bush Key , Dry Tortugas , coll. Bartsch, Jun.1921; 4 males (17.1–7.3 × 24.9– 10.5 mm), 3 females (12.2–8.1 × 18.3– 11.9 mm) ( ZRC 1984.6119 – 6125 ), Barbados, River Bay , under stones, littoral, coll. M. Telford, 23 Aug.1974; 2 dried males, 1 dried female ( MMUS – C 1984–1986 ); 2 dried males, 6 dried females ( MMUS – C 1975–1982 ).

Type locality. – Jamaica .

Diagnosis. – Carapace transversely hexagonal, tuberculated, tubercles may be joined in twos or threes, pubescent anteriorly. Hepatic region separated by transverse groove extending from second anterolateral spine; tuberculated anterolaterally. Branchial region weakly separated into two anterior portions by oblique groove. Front with two transverse ridges immediately behind frontal margin, may be denticulated externally. Orbit completely denticulated; external and internal orbital spines present; supraorbital and margins each with two longitudinal fissures. Anterolateral margin convex, with six or seven acute spines. Surface of third maxilliped minutely granulated, sparsely pubescent. Pterygostomial region pubescent, minutely granulated. Suborbital region slightly denticulated. Chelipeds tuberculated, tubercles rounded, produced forward in longitudinal rows; anterior margin of merus pubescent, surfaces minutely granulated; carpus with acute tubercles distally, prominent acute spine present at inner margin, with a smaller one further below ventral surface; chela covered with acute tubercles in longitudinal rows, tubercles may be present on dactylus; tubercle rows on major chela reduced in numbers posteriorly. Anterior male thoracic sternum minutely granulated anteriorly. G1 relatively short, stout, long spinules present at inner edge, extending some distance from tip to basal portion; sinuous at tapered acute tip; slightly pubescent on outer edge.

Remarks. – Zimsen (1964) states that the type specimen(s) in London are lost, but it is clear that the present specimen in the ZMUC is part of the collection of Banks and is thus part of the original, i.e. type series examined or used by Fabricius. It was probably given to Fabricius subsequently and retained in the ZMUC. As such, the present specimen is clearly a syntype, and is here designated as the lectotype of Cancer gonagra . Dana (1952a) described Eriphia armata from Patagonia, but on the basis of his description and figures ( Dana, 1852a, b, 1855), there seems little reason not to regard it as conspecific with E. gonagra .

Superficially, E. gonagra , E. squamata and E. granulosa resemble each other, with regards to the carapace shape, tuberculation on the carapace and chelipeds, orbits, shape of anterolateral spines etc. Rathbun (1930) constructed a key to separate them with the use of tubercular arrangement and male first pleopods. On closer examination, there are other characters that can also serve to distinguish them. Eriphia granulosa can be easily separated from its two allied species by having a prominent deflexed front and two inflated frontal lobes. Apart from Rathbun’s (1930) use of the G1 to distinguish E. gonagra and E. squamata , several other characters can also be utilised with some confidence. Tubercles on the outer surface of the chela of E. gonagra are rounded and distributed sparsely; while those on E. squamata are flattened and densely packed in longitudinal rows. The anterior male thoracic sternum of E. gonagra is minutely tuberculated without tufts of setae while in E. squamata , this structure is smooth with scattered tufts of setae. The male abdomen of E. squamata is also very narrow compared to that of E. gonagra , with both lateral margins distinctly concave. Lastly, as highlighted by Rathbun (1930), the tip of the G 1 in E. gonagra is acute with the subterminal part slightly bent while that of E. squamata is rounded and shaped like a golf club.

Stimpson (1860) quoted from Dr. Cooper that these crabs “… built nests of mud upon branches and roots of the mangroves at the edge of water”. Garth (1978) further commented that they are abundant and can invariably be taken by hand sampling on the rocky shores. Holthuis (1959) expressed doubts with regards to records of the species from Surinam, noting that the muddy coastlines of the country were unsuited to the species.

Rathbun (1900) noted that E. gonagra are always bright in colour: some reddish-brown while others yellowish-brown in colour with darker patches. The light yellow coloured ambulatory legs are largely covered with fine red dots while the tuberculation on the upper surfaces of their claws are dark red in colour.

Distribution. – Western Atlantic Ocean, extending from Patagonia to Brazil, including Bermuda.

Figures

Fig. 2. Eriphia gonagra (Fabricius, 1781), male, 18.7 × 26.0 mm, NHM 1887.23: A, dorsal view; B, frontal view; C, chelipeds; D, ventral view.

Fig. 3. Gonopods: A–C, Eriphia verrucosa (Forskål, 1775), male, 50.6 × 60.4 mm, USNM 152249. D–F, E. gonagra (Fabricius, 1781), male, 26.0 × 18.7 mm, NHM 1887.23: A, D, G1s; B, E, distal part of G1s; C, F, G2s. Scale bars = 1.0 mm.

Fig. 6. Eriphia granulosa A. Milne-Edwards, 1880, male, 10.0 × 14.9 mm, USNM 78218: A, dorsal view; B, frontal view; C, chelipeds.

Fig. 5. Eriphia granulosaA. Milne-Edwards, 1880, holotype female (dried), 12.0 by 17.0 mm, MNHN 2447S. A, dorsal view; B, right chela; C, left chela.