Description of the egg capsule of Atlantoraja castelnaui (Elasmobranchii, Rajidae)

• Published in: Brazilian journal of oceanography Vol. 56; no. 1; pp. 65 - 68
• Main Authors: Oddone, María Cristina, Mesa, Alejo, Amorim, Alberto Ferreira de
• Format: Journal Article
• Language: English
• Published: Universidade de São Paulo 01-03-2008
• Subjects: Atlantoraja; Atlantoraja castelnaui; Cyclophora; Elasmobranchii; Marine; Rajidae; ASW, Brazil, Rio de Janeiro; PSW, Argentina
• ISSN: 1679-8759; 1679-8759; 1982-436X
• DOI: 10.1590/S1679-87592008000100007

Skates (Rajidae) are oviparous and lay their eggs on the sea floor. Their large horny capsules are synthesized and secreted by the nidamental gland (WOURMS, 1977; WOURMS et al., 1988). The egg capsule is the tertiary cover of the egg in oviparous elasmobranchs and protects the embryo development in the sea bottom, as no parental care exists in this group. The genus Atlantoraja MENNI, 1972 is endemic to the South-western Atlantic (COMPAGNO, 2005). Atlantoraja castelnaui (MIRANDA RIBEIRO, 1907) ranges from Rio de Janeiro State (Brazil) to Argentina, and is more common in the southernmost limit of its distribution (FIGUEIREDO, 1977) where it is captured at depths of 25-220 m (VOOREN, 1997). In Uruguayan waters, males of this species attain sexual maturity at total lengths of 91-95 cm and females at 110-114 cm (ODDONE et al., 2005). Description of the egg capsules for the congeneric species A. platana and A. cyclophora are available in the literature (ODDONE et al., 2004; ODDONE, 2005). The aim of the present work is to describe the egg capsule of A. castelnaui, a species subjected to intense fishery and commercialization in its distributional range.