Grey mullets (family Mugilidae)
Though the popular name ‘mullets’ generally refers to the species of the family Mugilidae, the name grey mullet is used to distinguish them from the red mullets of the family Mullidae. The taxonomic classification of the grey mullets has been rather confusing, and the many revisions of the family have not made it any easier for aquaculturists to identify the various species. Jhingran and Gopalakrishnan (1974) have listed 13 valid species belonging to the genus
Mugil and one species of the genus Rhinomugil which have been used in aquaculture. Though some authors have used the generic name Liza, based on the extent of development of the adipose eyelids, others consider this classification invalid as this characteristic is not of diagnostic value (Pillay, 1962). The other genus considered valid, namely Rhinomugil, is represented by the species Rhinomugil corsula, which is of some importance in Indian fish culture. So in the following account of grey mullet culture the candidate species will be treated as belonging to the two genera, Mugil and Rhinomugil.
The most widely distributed and well-known species of grey mullet is Mugil cephalus, some-times referred to as the striped mullet (fig. 21.1). Because of the fast growth rate and the
comparatively large size of the adults, this has been the species of choice in all areas. But fry and fingerlings of M. cephalus are not as abundantly available as those of the other species. So in countries bordering the Mediterranean, M. capito, M. auratus (fig. 21.2), M. saliens (fig.21.3) and M. chelo are also utilized in extensive or intensive farming. Other species used in the Indo-Pacific region are M. parsia (= dussumieri), M. tade, M. macrolepis, M. so-iuy and R. corsula. Additional species of importance inSouth America are M. curema and M. brasilien-sis. Experimental work in West Africa hasalso included the species M. falcipinnis and M. grandisquamis.