Morphometric And Electrophoretic Analyses Of Grey Mullets In Benya Lagoon And Kakum Estuary
Abstract
A comparative study of populations of grey mullets from Benya lagoon and Kakum estuary was carried out from October, 2013 to May, 2014. Three taxonomic methods were used to characterize the species. Five species were encountered during the period of study. These were Liza falcipinnis, Liza grandisquamis, Liza dumerilii, Mugil cephalus and Mugil curema. According to this study, the discriminating traits of mullets are head depth, body depth, caudal peduncle length, caudal peduncle width, ocular diameter, anal fin base length, interdorsal space length, pre orbital head length, post orbital head length, 2nd dorsal fin height and anal fin height. Traits such as HD, IDS, AFH, HL/HD, HD/BD, OD/HD and PREOHL appear to be specific for intergeneric differentiation. All morphometric ratios used in this study seemed to be key identification traits of grey mullets. Within the family Mugilidae, members of the genus Liza appeared to exhibit more distinct morphospecies characteristics than members of the genus Mugil. There was marked variation between L. grandisquamis populations in both water bodies indicating possible subspecies level segregation. L. randisquamis from Benya lagoon and L. dumerilii from Kakum estuary appeared to share similar morphological features. A single population of M. curema from Benya lagoon seemed to exhibit similar morphological features with populations of M. cephalus, an indication of possible structural modification among the Mugils. All taxonomic protocols used revealed some level of variability, however, geometric morphometrics showed high sensitivity.
