Reproductive biology of turbot (Psetta maxima) and brill (Scophthalmus rhombus) (Teleostei, Pleuronectiformes) in the Adriatic Sea

The reproductive biology of two commercially important flat Fish, turbot (Psetta maxima) and brill (Scophthalmus rhombus), in the Adriatic Sea was investigated by histology and macroscopic analysis of gonads. Different patterns of vitellogenesis and spawning were observed in the two species. In turbot. gonad development culminates annually from March to May and the seasonal egg hatch develops synchronously. the eggs becoming ready at about the same time. In brill, the ovary contains several oocyte batches in different stages of maturity, indicating intermittent release of ripe eggs in the course of a long spawning season (January-July). These data are discussed and compared with observations on reproduction of turbot and brill for other areas of their distribution ranges.