Reproductive biology of king weakfish, Macrodon ancylodon (Perciformes, Sciaenidae) from the northeastern coast of Brazil

The reproductive biology of Macrodon ancylodon, a commercially important fish widely distributed along South America's Atlantic coast, is described from 240 specimens collected in northeastern Brazil. Specimens ranged from 18.2 to 33.5 cm in length, exhibiting positive allometry. Total length at first sexual maturity was 21.13 cm. M. ancylodon has an asynchronous gonadal maturation and would be a batch spawner within a reproductive period. Total weight and length of females do not affect the relative fecundity values in this species. Analysis of the gonadosomatic index, condition factor and frequency of maturational stages shows that M. ancylodon was capable of reproducing throughout the year, despite the fact that spawning peaks were observed during November-December and August-September. The results are evidence that the study area is used by M. ancylodon for reproduction. The data will also be important for the development of stock management strategies.