Allozyme variation in a Johnston's topminnow, Aplocheilichthys johnstoni, population from the Zambezi River system

Twenty five specimens of Aplocheilichthys johnstoni (Günther, 1893) were collected from the Cuando River in the Zambezi River system. Protein electrophoresis was used to analyse the genetic structure of this population. Seven of the 20 loci studied, (15% using the 95% criterion) revealed polymorphism. The heterozygosity value obtained (HO = 0.050) compare favourably to those recorded for other fish species. Observed allele frequencies deviated from expected Hardy-Weinberg proportions at the EST-3, GPD-1 and GPI-2 protein coding loci. The results from the genetic analysis of A. johnstoni are discussed in relation to its role in mosquito larval control. WaterSA Vol.27(1) 2001: 53-5