Researches on the morphology of embryonic development of red snapper, Lutjanus erythopterus

In order to provide the reference for the artificial propagation and breeding, the morphological process of early embryonic development of red snapper(Lutjanus erythopterus) was surveyed directly by microscopy in this paper. The early embryonic morphogenesis process of red snapper can be divided into 6 stages, including fertilized eggs, cleavage,blastula, gastrula, neurula and organ formation, and 24 periods. The fertilized egg of red snapper is the floating egg,transparent and spherical in shape, with a large oil granule. Under the conditions of water temperature 28 ℃ and salinity32.2, the egg plasm began to concentrate towards the animal pole of the egg and formed a blastoderm, 15 min after fertilization. It began of the first cleavage, 30 min after fertilization, as discoidal cleavage. 3 h after the fertilization,embryo entered the high blastula stage and 5 h 42 min after the fertilization, the blastoderm in the yolk was gradually extended to the surrounding and became the low blastula stage. 6 h 27 min after the fertilization, the embryo developed into the gastrula stage. 9 h 36 min after the fertilization, the neural plate formed. Then, the neural plate changed into neural tube. The front of the neural tube expanded into 3 brain vesicles, namely, forebrain, midbrain and hindbrain. After the brain vesicles differentiated, the optic vesicles, otic vesicle and lens formed in succession. The caudal bud appeared15 h 32 min after the fertilization and about 20 h after the fertilization, a large number of larvae hatched.