The microscopic structure of the egg capsules of Atlantoraja cyclophora, a species endemic to the Atlantic region of South America, is presented in this paper. In a transverse section, the dorsal face of the egg case is 70mu in width, and is subdivided into four layers. Ventrally, the egg capsule wall is 60 mu wide and composed of three layers. Both faces are covered by prickles which render the egg capsule surface striated to the naked eye.
rajoids; egg capsules; Atlantoraja cyclophora; oviparity
