First report and description of a legskate, genus Cruriraja, from the southwestern Atlantic Ocean (Chondrichthyes: Rajidae

de Carvalho M.R., Gomes U.L., McEachran J.D.

Date de parution: décembre 2006
Volume: 30
Number: 4
Pagination: 343-354
Editeur: Société Française d'Ichtyologie

A female 320 mm in TL and presumably immature is described here as the first specimen of legskate, genus Cruriraja Bigelow & Schroeder, 1948, collected in the western South Atlantic Ocean; the specimen was taken from the eastern Brazilian continental slope off the state of Bahia in a depth of 251 m. It is morphologically characterized and compared to all congeners, and is identified as Cruriraja rugosa Bigelow & Schroeder, 1958, a species that otherwise occurs in the western North Atlantic Ocean, Gulf of Mexico, and Caribbean Sea. Our specimen shares with C. rugosa features not present in congeners (e.g., a single clearly defined row of thorns on posterior dorsal disc and tail midline, absence of scapular thorns), but differs from typical C. rugosa in lacking a distinct caudal fin, in having fewer thorns on tail midline and sides, in lacking denticles on ventral tail surface, and in snout angle; these characters are considered insufficient, however, to describe the unique Brazilian specimen as a new species. Species of Cruriraja are otherwise restricted to the lower continental shelf and slope of the western North Atlantic Ocean, Gulf of Mexico, Caribbean Sea, Indian Ocean, and off South Africa. The Brazilian specimen reduces the distributional void between South African/Indian Ocean species of Cruriraja with those occurring in the Caribbean Sea, Gulf of Mexico and western North Atlantic Ocean.

Mots-clés: ASW - Caribbean Sea - Cruriraja - distribution - Gulf of Mexico - Rajidae - Taxonomy
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