Low genetic differentiation among morphologically distinct Labeobarbus species (Teleostei: Cyprinidae) in the Lake Victoria and Albertine basins, Uganda: insights from mitochondrial DNA

  • VB Muwanika
  • MF Nakamya
  • J Rutaisire
  • B Sivan
  • C Masembe

Abstract

Labeobarbus altianalis and L. bynni bynni are hexaploid cyprinid fishes in the genus Labeobarbus. In the Great Lakes region of Africa, these two large-bodied barbs exhibit considerable morphological variations. Their intraspecific classification, currently based on geographical distribution and morphological variation, is of limited application due to the overlapping nature of the water systems. Patterns of genetic variation in the Albertine and Victoria drainage basins in Uganda were assessed using mitochondrial sequences of the control region (470 basepairs) and the cytochrome b gene (627 basepairs). At the control region 36 distinct haplotypes were observed in a total of 177 individuals. Relatively low overall nucleotide diversity (π = 0.010) was observed. Hierarchical analysis of the molecular variance revealed significant differentiation between populations in the total sample (FST = 0.172, p < 0.001), among populations within each basin (FSC = 0.047, p < 0.001), but no significant subdivision among basins (FCT = 0.131, p > 0.05). Phylogenetic analysis of the control region haplotypes resulted in a star-shaped phylogeny, with no clusters that reflect current taxonomic designation, morphotypes or basins. Phylogenetic analysis of cytochrome b gene sequences resulted in a tree topology similar to that observed for the control region. Thus the morphological characteristics separating the two species are intraspecific variation and the whole sample probably belongs to the same species.

African Journal of Aquatic Science 2012, 37(2): 143–153

Author Biographies

VB Muwanika
Molecular Biology Laboratory, Institute of Environment and Natural Resources, Makerere University, PO Box 7298, Kampala, Uganda
MF Nakamya
Department of Anatomy, Faculty of Veterinary Medicine, Makerere University, PO Box 7062, Kampala, Uganda
J Rutaisire
Aquaculture Research and Development Centre, Kajjansi, PO Box 530, Kampala, Uganda
B Sivan
Department of Animal Sciences, The Hebrew University of Jerusalem, Rehovot 76100, Israel
C Masembe
Molecular Biology Laboratory, Institute of Environment and Natural Resources, Makerere University, PO Box 7298, Kampala, Uganda
Section
Articles

Journal Identifiers


eISSN: 1727-9364
print ISSN: 1608-5914