Embryonic, Larval, and Early Juvenile Development of the Tropical Sea Urchin, Salmacis sphaeroides (Echinodermata: Echinoidea)

Table 1

Embryonic developmental events of S. sphaeroides. Three replicate fertilization experiments were conducted and for each developmental stage, 10 embryos from each replicate were used for the observation and measurement of embryos.

Time after insemination	Developmental stages	Diameter (μm)
00.01 h	Fertilized eggs with the formation of fertilization membrane	134.86 ± 5.35
00.05 h	Fertilized eggs with complete fertilization membrane	134.86 ± 5.35
01.12 h	2-cell stage	154.27 ± 7.17
02.03 h	4-cell stage	157.14 ± 5.84
02.28 h	8-cell stage	159.25 ± 6.29
02.51 h	16-cell stage	161.10 ± 5.80
03.12 h	32-cell stage	163.65 ± 4.78
03.32 h	Multicell (Morulla) stage	164.38 ± 4.48
08.45 h	Hatching Blastula	174.72 ± 4.43