Embryonic-larval development and some data on the reproductive biology of Abudefduf sexfasciatus (Pomacentridae: Perciformes)

Abstract

The embryonic-larval development is described and some data on the reproductive biology of Abudefduf sexfasciatus are provided. This species is characterized by an intermittent spawning. The egg membranes of ovulated oocytes are represented by one-layered zona radiata and a shaggy chorion situated at the animal pole. Spermia have one flagellum with a length of about 25 μm. The shape of the head resembles a bean. The duration of movements of spermia up to their complete stop is about 1 h at a temperature of 23–25°C. The drawings and morphological descriptions of the stages of normal development at a constant temperature of 25°C are presented. The duration of the incubation period is about 120 h. By the moment of hatching, an almost complete resorption of yolk takes place, and the larva is ready to pass to an exogenous feeding. Soon after emerging from egg envelopes, A. sexfasciatus exhibit a clearly pronounced positive phototaxis.