EMBRYONIC AND YOLK-SAC LARVAL DEVELOPMENT OF THE SPARID DENTEX (DENTEX) DENTEX (LINNAEUS, 1758)

Embryonic and yolk-sac larval development of laboratory spawned common dentex. Dentex (Dentex) dentex (Linnaeus, 1758), is described and ill ustrated. The ripe egg of D. dentex is a typical sparid egg with mean diameter of 958 mu m. The incubation period was 81 h at 17 degrees C. Newly hatched yolk-sac larvae were 2170 +/- 200 mu m in total length. Some morphological characteristics which may be useful for identificat ion are described and compared with some other sparid yolk-sac larvae. The distance of the wide pigment spot in the middle of the tail from the anterior tip of the body was about 1680 mu m in newly hatched yolk -sac larvae, and about 2365 mu m 48 h after hatching. Common dentex yo lk-sac larvae could be distinguished by the distance of the terminal s ection of the gut from the posterior end of the yolk sac. In newly hat ched yolk-sac larvae it was about half the oil globule diameter length , and in yolk-sac larvae older than 24 h this distance was the same as the oil globule diameter. Three days after hatching this distance was more than twice the oil globule diameter. The distance of the termina l section of the gut could be a reliable parameter for distinguishing dentex larvae from other sparid yolk-sac larvae in ichthyoplankton stu dies.