A 4-year study (May1997^December 2000 of the reproductive biology of pink dentex Dentex gibbosus (Ra¢nesque) from the Adriatic Sea revealed that this species is a rudimentary hermaphrodite. The smallest mature males and females captured were 38.70 cm in total length (T L ) and 39.80 cm in total length (T L ) respectively. The von Bertalan¡y growth parameters estimated for the entire population were: L 1 5107.24, K 5 0.12 and t 0 5 À 0.90. Fifty per cent of the population were sexually mature at 41.50 cm T L , while 100% of the specimens were sexually mature at 57.00 cm T L . Both monthly gonadosomatic index and macroscopically determined gonad stages strongly indicate that the pink dentex from the Adriatic Sea spawn partially in August, September and October. The mean value of absolute fecundity (F) was 1672 Â 10 6 eggs. The results of great fertility of the pink dentex, partial spawning and relatively late sexual maturation suggest that the pink dentex has a high potential for commercial culture.
The fecundity of the Black Sea bream from the eastern middle Adriatic (Croatian coast) was assessed by the volumetric method using 59 ovaries in pre-spawning stage from fish between 18.5 and 33.5 cm total length. Estimates of total potential annual fecundity varied between 31,670 and 554,070 eggs per female. Relationships between total potential fecundity and total length (TL), total weight (TW) and age (A) were established using the multiplicative regression model. Relative fecundity is constant, reaching a maximum of 850 eggs per g in the 30.5 cm to 31.0 cm length class.
The embryonic and early larval development of the laboratory-reared tub gurnard, Trigla lucerna are described. The eggs ranged in diameter from 1·33 to 1·40 mm, with a mean of 1·36±0·236 mm, were pelagic and spherical with a homogeneous and unsegmented yolk. There was single oil globule in the eggs. Globule ranged in diameter from 0·25 to 0·29 mm (mean 0·28±0·012 mm). Embryonic development lasted 115 h 2 min at mean temperature 13·5 °C. Newly-hatched larvae were 3·09±0·014 mm in total length. Absorption of the yolk sac was complete after the sixth day, when larvae reached 4·85±0·015 mm in total length. The only character for identifying eggs among species could be diameter, since the values obtained are lower than those obtained for Eutrigla gurnardus and Aspitrigla cuculus, but larger than those for Trigloporus lastoviza. The length of newly hatched yolk-sac larvae of tub gurnard is significantly lower (t-test, P<0·05) than those of most of the other gurnard species. Characters likely to help in identification of species will probably prove to be the length, shape and pigmentation of the pectoral fin, and the degrees of development of spiny armature on the head.
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