Egg and early larval development of laboratory reared dusky grouper, &lt;i&gt;Epinephelus marginatus&lt;/i&gt; (Lowe, 1834) (Picies, Serranidae)

Branko Glamuzina,Miro Kraljevic,Valter Kozvul,Niksa Glavic,Bosko Skaramuca,Jakov Dulcic

doi:10.3989/scimar.1998.62n4373

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.

Highlights

The dusky grouper, Epinephelus marginatus (Lowe, 1834), is distributed throughout the Mediterranean Sea, and in the Atlantic, from the coast of the British Isles to Southern Africa, and along the coast of Southern Brazil
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

Summary

Introduction

The dusky grouper, Epinephelus marginatus (Lowe, 1834), is distributed throughout the Mediterranean Sea, and in the Atlantic, from the coast of the British Isles to Southern Africa, and along the coast of Southern Brazil. It inhabits rocky bottoms, from shallow waters to depths of 50 meters and lives in caves of stone blocks, where it spends most of its time (Jardas, 1996). In recent times, spawned eggs have been described (Barnabe, 1974 : Zabala et al, 1997). Little data whatsoever are available regarding larval stages, except for the description by Barnabe (1974), and one picture of larva published later (Zabala et al, 1997)

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Conclusion