Amphithrax verrucosus (H. Milne Edwards, 1832 )

Parasram, Nadeshinie, Santana, William & Vallès, Henri, 2023, Checklist of the shallow-water marine Brachyura (Crustacea: Decapoda) of Barbados, West Indies, Zootaxa 5314 (1), pp. 1-62 : 21-22

Amphithrax verrucosus (H. Milne Edwards, 1832)

( Fig. 9D )

Mithrax verrucosus H. Milne Edwards, 1832: 11 , pl. 4 [type-locality: Martinique; type in MNHN]; Schomburgk 1848: 65; Stimpson 1860: 187; Desbonne in Desbonne & Schramm 1867: 6; A. Milne-Edwards 1875: 102; Miers 1886: 86; Rathbun 1897: 9; Nutting 1919: 77; Rathbun 1921: 83; 1924: 20; 1933: 30; Rodriguez 1980: 287; Abele & Kim 1986: 524–525, figs. c–d; Melo 1996: 239, unnumbered fig.; Alves et al. 2012: 943, fig. 3C; Lira et al. 2013: 55, tab. 1; Carmona-Suárez & Poupin 2016: 373, fig. 6I.

Mithrax (Mithrax) verrucosus .— Young, 1900: 93; Rathbun 1925: 400, pl. 144; Boone 1927: 39; Williams 1965: 255, figs. 235, 245B; Coelho & Ramos 1972: 215; Collins & Morris 1976: 119, pl. 17, fig. 7, pl. 18, figs. 5–7; Powers 1977: 58; Williams 1984: 336, figs. 271, 275c; Keith 1985: 259, fig. 5E; Wagner 1990: 29–32, figs. 32–35.

Mithrax plumosus Rathbun, 1901: 67 .

Amphithrax verrucosus .— Poupin 2018: 193, fig. 211.

Distribution. Western Atlantic: USA (South Carolina), Cuba, Jamaica, Puerto Rico, Gulf of Mexico, St. Thomas, St. John, St. Martin, Antigua, Guadeloupe, Isla de Aves, Martinique, Barbados, Grenada, Tobago, Trinidad, Isla de Blanquilla, Isla de Margarita, Isla de Cubagua, Tortuga, Los Roques, Bonaire, Curaçao, Aruba, Colombia, Venezuela, and Brazil ( Rathbun 1897; Rathbun 1901; 1921; Carmona-Suárez & Poupin 2016; Poupin 2018).

Material examined. Barbados, Drill Hall , St. Michael, nearshore rubble, 13°4’36.30”N, 59°36’26.63”W, 2 ♀, 3 Ô CW: 27.1, 11.3, 11.1, 13.1, 11.1 mm ( BLSZ 123 ) . Batts Rock , St. Michael, subtidal, 13°8’04.81”N, 59°38’12.30”W, 1 Ô CW: 26.7 mm ( BLSZ 165 ) . Idem , 1 Ô CW: 40.5 mm ( MZUSP 40921 ) . Coconut Court , Christ Church, nearshore rubble, 13°04’31.59”N, 59°36’13.78”W, 2 Ô, 4 ♀ (1 ovig.) CW: 21.7, 11.7, 22.6, 16.4, 24.5, 23.3 mm ( BLSZ 211 ) . Idem , 1 Ô, CW: 41.6 mm ( BLSZ 218 ) .

Remarks. Specimens of Amphithrax verrucosus were collected in nearshore rubble habitat at low tide and caught in crab traps (~ 4 m deep). This species is very abundant in nearshore rubble habitat on the south and west coasts of Barbados. Amphithrax verrucosus was collected under the same rubble rock as A. aculeatus , Mithraculus coryphe (Herbst, 1801) , Mithraculus forceps A. Milne-Edwards, 1875 , Eriphia gonagra , and Pachygrapsus transversus ( Gibbes, 1850) . One ovigerous female was collected in June 2021. First report for Barbados was made by Schomburgk (1848: 65) as Mithrax verrucosus , and specimens are stored at the NHM. Rathbun (1921: 83) reported one juvenile male specimen of Mithrax (Mithrax) verrucosus collected by the Barbados-Antigua Expedition in 1918 (USNM 72681) and reported this specimen as a first record for Barbados, which is not the case, since this species was previously reported for Barbados by Schomburgk (1848). Another specimen (one male, USNM 72597) was also collected during this expedition. Collins & Morris (1976) collected fossilised specimens of Amphithrax verrucosus H. Milne Edwards, 1832 , from Pleistocene and Pliocene coral rock formations at several locations in Barbados. Jones (1969: 381) also reported A. verrucosus for Barbados; specimens were collected from Bathsheba on the east coast. This study did not collect any specimens of A. verrucosus from the east coast of Barbados.

Windsor & Felder (2014: 163) included Amphithrax verrucosus as a junior subjective synonym of Amphithrax aculeatus ; however, we prefer to be conservative and follow the opinions of Ng et al. (2008: 123), Carmona-Suárez & Poupin (2016: 372; figs. 7 A, B) and Poupin (2018: 192–193; figs. 210, 211) (see remarks for Amphithrax aculeatus above), which considers A. verrucosus as a valid species. Amphithrax verrucosus can be identified by the smooth upper margin of the palm of the chelipeds, the lack of spines on the propodus of ambulatory legs, and the presence of one spine and two granules on the ventral surface of the merus of chelipeds in juvenile specimens (modified from Wagner 1990).

Genus Mithraculus White, 1847

Figures

FIGURE 9. Superfamily Majoidea Samouelle, 1819, dorsal habitus:A, Stenorhynchus seticornis (Herbst, 1788), female (ovig.), cw 9.1 mm (BLSZ 135); B, Amphithrax aculeatus (Herbst, 1790), male, cw 41.6 mm (BLSZ 214); C, Amphithrax hemphilli (Rathbun, 1892), male, cw 4.5 mm (BLSZ 043); D, Amphithrax verrucosus (H. Milne Edwards, 1832), male, cw 41.6 mm (BLSZ 218). Scale bars: A, B, D = 20 mm; C = 5 mm.