Embryonic and larval development of the thicklipped mullet ( Chelon labrosus) under controlled reproduction conditions

Abstract

This paper describes the embryonic and larval developmental stages of Chelon labrosus, a prominent species among the Mugilidae, a family of high interest in the ecological management of coastal extensive aquaculture systems. Its high commercial value makes it the most important mullet in the Italian northern Adriatic “vallicoltura”. The success of induced reproduction techniques enabled us to describe its developmental stages, which were recorded by camera lucida drawings and presented as developmental tables. Histological and scanning electron microscopy observations were also carried out. Development may be divided into four periods: embryonic, pre-larval, larval and juvenile, each one characterized by typical anatomical and physiological features. At hatching, C. labrosus larvae are rather underdeveloped, in comparison with other marine farmed species, but the sense organs develop rapidly as well as the mouth. At 12 days the larva already has a juvenile head on a larval body. The juvenile stage is reached precociously, at 60 days, so that C. labrosus had a high performance in the rearing trials which were carried out.