Gamete ultrastructure in some species of the family Mullidae from the South China Sea

Abstract

In tropical representatives of the family Mullidae, the ultrastructure of oocyte envelopes (Parupeneus multifasciatus and Upeneus tragula) and spermatozoa (P. multifasciatus and P. barberinoides) is studied. The egg envelopes include the single-layered zona radiata and weakly expressed chorion. The spermatozoa are characterized by the presence of the oval head flattened on a side and deep nuclear fossa reaching approximately 90% of the head length. The centriolar complex and basal part of the flagellum are located inside the nuclear fossa.