No abstract

The embryonic development of Cuban gar (Atractosteus tristoechus) was described under controlled laboratory conditions. During the whole embryogenesis seven periods were defined: the zygote (0-½ h), cleavage (¾-4 h), blastula (5-10 h), gastrula (12-20 h), segmentation (24-40 h), pharyngula (48-66 h) and hatching (72-96 h) periods. The stages were based on morphological features, generally readily identified by examination of the embryo with the dissecting stereomicroscope. Hatching occurred 96 ± 4 h after spawning at 28°C.