Abstract
Egg capsules of Atlantoraja cyclophora and A. platana are asymmetrical, dorsally convex and ventrally flat, with longitudinally striated faces. Those of other rajoid genera occurring in Cassino Beach (Rio Grande do Sul State, Brazil), Psammobatis, Sympterygia and Rioraja, are equally convex in lateral view, and have smooth faces. In Atlantoraja the egg capsules are laterally keeled while in Sympterygia a lateral flange exists. Mean egg capsule length and width are 68 and 39 mm in A. cyclophora, and 69 and 45 mm in A. platana. Egg capsules of A. platana are significantly wider than those of A. cyclophora with anterior and posterior horns significantly longer. The outline of the velum is convex in dorsal view in A. cyclophora and slightly convex in A. platana.References
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