Phenotypic features depict variability in <i>Clarias jaensis</i> wild populations in Cameroon Variability in <i>Clarias jaensis</i> in Cameroon

Abstract

This study was conducted to contribute to a better understanding of the phenotypic diversity of natural populations of Clarias jaensis in Cameroon, with the objective to harness the exploitation and conservation of this native catfish. A total of 269 native catfish (Clarias jaensis), including 139 males and 130 females, were sampled on 6 sites in Cameroon. One (1) phaneroptic observation, seventeen (17) biometric traits and four (4) meristic traits were evaluated. The main results showed that there are three colour patterns (brown, black and marbled) on the dorsal region and flanks in Clarias jaensis, with a predominance of brown (81.04%) and black (11.52%) patterns. The effect of sex on total weight (TW), snout length (SnL), prepelvic length (PPvL), total length (TL), standard length (SL), body depth (BD) and caudal peduncle depth (CPD) was significant (p<0.05). In general, biometric traits were significant (p<0.05) and positively correlated with total weight. The number of soft fin rays in dorsal fin (D) and anal fin rays (A) were negatively and weakly correlated with total weight (r=-0.02 and r=-0.04 respectively), while, the number of soft fin rays in pectoral fin was negatively and weakly correlated with total weight (r=0.13). The Principal Component Analysis (PCA) performed on all the biometric and meristic traits shows that the first two axes alone account for more than 50% of the total inertia. Hierarchical Ascending Classification (HAC) highlighted the existence of 3 morphotypes. The observed biodiversity suggests that the Clarias jaensis catfish is a natural genetic resource with the necessary variability to be exploited, though there is a need to develop population and habitats monitoring plan.