Megalobrachium mortenseni Haig, 1962

Ferreira, Luciane Augusto De Azevedo & Melo, Gustavo Augusto Schmidt De, 2016, Porcelain crabs from Brazil (Crustacea: Decapoda: Anomura: Porcellanidae), Zootaxa 4092 (2), pp. 175-194 : 176-177

Megalobrachium mortenseni Haig, 1962

( Fig. 1 A)

Megalobrachium mortenseni Haig, 1962: 189 , figures 2–5 (type-locality: Virgin Islands, northwest of St. John, west of Congo Cay).

Material examined. Brazil: Bahia—Abrolhos, 1 female (MZUSP-10652); Recife de Popa Verde, 3 males, 1 female (MNRJ-6782). Espírito Santo – Piúma, 20°50’578”S, 40°28’553”W, 21.5 m, 3 males, 1 ovigerous female (MZUSP-24529). Rio de Janeiro—Ilha Grande, Praia do Furão, 1 male (MNRJ-3646); Cabo Frio, Búzios, Praia da Armação, 1 male (MNRJ-3816). São Paulo—São Sebastião, Praia do Porto, 1 ovigerous female (MZUSP-9531).

Recognition characters. Carapace rounded, as long as broad in males, slightly broader than long in females; quite eroded; lateral margins with crenulate crest; protogastric ridge and cervical groove evident; gastric region elevated, posterolateral region plicated. Pterygostomial flap of carapace with median longitudinal serrate crest. Front with serrate margin. Chelipeds equal, eroded and covered with small rounded tubercles; merus rugose, with small, serrate distal lobe on flexor margin; carpus with 4 longitudinal crenulate carinae, small lobe in proximal third on flexor margin; propodus with 3 longitudinal crenulate carinae; dactylus with 1 longitudinal crenulate carina. Walking legs slender, carpus with 2 serrate crests on extensor margin; propodus with 5 spines on flexor margin, dactylus with 4 spines on flexor margin. Gonopods present in males. Telson composed of 7 plates.

Habitat. Intertidal region down to depths of 30 meters, usually on rocky substrates.

Geographic distribution. Western Atlantic—Honduras, Roatán, Bay Islands; Panama, Bocas del Toro and Limón Bay; Virgin Islands, St. John; Colombia, Santa Marta and Rosario Islands; Venezuela, Margarita Island; and Brazil (Pará to São Paulo).

Figures

FIGURE 1. Preseved specimens, dorsal view. A, Megalobrachium mortenseni Haig, 1962, ovigerous female (MZUSP- 24529); B, Megalobrachium roseum (Rathbun, 1900), female (MZUSP- 19905); C, Megalobrachium soriatum (Say, 1818), male (MZUSP- 19903); D, Minyocerus angustus (Dana, 1852), ovigerous female (MZUSP- 17473); E, Pachycheles ackleianus A. Milne-Edwards, 1880, male (MZUSP- 19548); F, Pachycheles chubutensis Boschi, 1963, male (MZUSP- 7194); G, Pachycheles greeleyi (Rathbun, 1900), male (MZUSP- 21232); H, Pachycheles laevidactylus Ortmann, 1892, male (MZUSP- 18723). Scales: A – E (1 mm); F – H (5 mm).