Egg and early larval development of laboratory reared dusky grouper, Epinephelus marginatus (Lowe, 1834) (Picies, Serranidae)

Abstract

The embryonic and early larval development of the laboratory-reared dusky grouper, Epinephelus marginatus (Lowe, 1834) are described and illustrated. The eggs, with a mean diameter of 846.68 ± 41 µm and a range from 736-940 µm, were spherical and transparent with transparent chorion. Embryonic development lasted 30 hours at 23°C. Newly-hatched larvae were 1.52 ± 0.066 mm in length. Absorption of the yolk sac was complete after the fourth day, when larvae reached 2.63 ± 0.123 mm in total length. The mouth opened 72 hours after hatching, and was in function after 96 hours, with an opening diameter ranging from 250-300 µm. Larvae had two fields of intensive pigmentation, one above the intestine, and the other between the anus and the end of the notochord.