Ultrastructure of sporogonial stages of Eimeria kayarensis Diouf and Toguebaye, 1994 (Apicomplexa, Coccidia)

Abstract

        The ultrastructure of sporogonial stages of Eimeria kayarensis (Coccidia, Eimeriidae) in the spiral valve of the brown ray, Raja miraletus L. (Pisces, Rajiformes), was studied. The oocysts had bilayered walls. Within the young oocysts were sporonts, surrounded by an electron dense wall with cytoplasm containing numerous amylopectin granules and some refractile bodies. The oocysts divided by plasmotomy into four sporoblasts. The young sporoblasts were enveloped by a unit electron dense wall that transformed into a thick sporocyst wall. The sporocysts were enveloped by a bilayered pellicle and possessed a Stieda body. Each mature sporocyst contained two sporozoites with numerous micronemes and two refractile bodies surrounded by amylopectin granules.