ABSTRACT
The study was carried out to examine the morphological parameters of fish in Ikpoba river, Southern Nigeria, from April, 2018 through September, 2018. Among the morphological parameters studied, Total Length (TL), Head Length (HL), Body Depth (BD) and Standard Length (SL) were measured. A total of 28 specimens comprising of 15 species were encountered in the study stretch. The species recorded include; Auchenoglanis monkei, Chromidotilapia guntheri, Clarias gariepinus, Clarias pachynema, Ctenopoma kingsleyae, Hemichromis bimaculatus, Malapterurus electricus, Parachanna obscura, Siluranodon, Synodontis courteti, Tilapia mariae, Xenomystus nigri, Chrysichthys walkeri, Brycinus nurse and Parachanna africana representing different families such as Claroteidae, Alestidae, Cichlidae, Claridae, Anabantidae, Malapteruridae, Channidae, Schilbeidae, Mochokidae, and Notopteridae. The mean total length values ranged from 12.25cm in Tilapia mariae to 17.5cm in Parachanna obscura. Clarias gariepinus had a mean value of 16.5cm, Ctenopoma kingsleyae had a mean value of 15cm while Clarias pachynema had a mean length value of 15.5cm. The following scale count were recorded for the fish species namely: Chromidotilapia guntheri, Ctenopoma kingsleyae, Parachanna obscura and Tilapia mariae. Scales counted include scales along the upper lateral line and scales along the lower lateral line for species with two lateral lines and scales counted in total for specie with one lateral line. Brycinus nurse possessed cycloid scales with smoothly rounded exposed surfaces and a thin circular disc-like edge; Similarly, the cycloid type with a larger exposed surface is exhibited in the scales of Chromidotilapia guntheri. Ctenoid scales with rough exposed edge was shown in Ctenopoma kingslayae. This study could be expanded and researched for a longer period to infer the maximum results from scale count of fish species in Nigeria. Nonetheless, this present study on the fish species of Ikpoba river is an important contribution to the fish data concerning head length (HL), body depth (BD), standard length (SL) and total length (TL) in Ikpoba river and Southern Nigeria.
