Staff directory
Jos Snoeks
Biology
Vertebrates
Vertebrates
Publication details
Bitja Nyom, A.R., Gilles, A., Pariselle, A., Bilong Bilong, C.F., Agnèse, J.F. & Snoeks, J. 2013. ‘Morphological, genetic and parasitological differentiations between four species of Hemichromis “five spots”: evidence on the existence of the new species from Central Africa’. Fifth International Conference of the Pan African Fish and Fisheries Association (PAFFA5). Book of abstracts.
Conference abstract
There are many contradictions about the identity, number and geographical distribution of species composing the Hemichromis “five spots” polyspecific complex. With this study we want to clarify some of the existing problems regarding the taxonomy and distribution of this species complex. From
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2007 to 2013 we sampled throughout the large distribution area of this species group, which runs from Senegal to Angola. Fresh or alcohol preserved specimens were identified phenotypically on the basis of their chromatic and morphometric characters, genetic differentiation was studied using the cytochrome b gene, monogenean gill parasites were studied to determine host-parasite co-speciation, and tree search analysis was performed under Maximum Likelihood, Parsimony, Distance and Bayesian Inference methods. Taxonomic congruence of these independent data sources suggests that there are at least four species in the examined Hemichromis “five spots” group. Morphologically, these species are distinguished by their phenotypic and morphometric characters. Hemichromis fasciatus Peters, 1858 is distributed widely in Western Africa, Hemichromis sp. “cameroon” is distributed in Lower Guinea from the Cross River to the Lobe River, H. elongatus (Guichenot, 1861) is distributed from the Ntem River to Angola including part of the Congo basin, and Hemichromis sp. “congo” is known from the Congo basin. There is an overlap zone including H. elongatus (Guichenot, 1861) and Hemichromis sp. “congo”. Hemichromis frempongi Loiselle, 1979 could be a fifth species, known from Lake Bosumptwi in Ghana. According to our results the Hemichromis “five spots” polyspecific complex contains more species than expected.