Molecular and morphometric data demonstrate the presence of cryptic lineages among freshwater crabs (Decapoda: Potamonautidae: Potamonautes) from the Drakensberg Mountains, South Africa
Abstract:The evolutionary importance of cryptic taxa is well documented, yet few studies have examined them with a view to conservation. In the present study, the significance of cryptic speciation in freshwater crabs is examined. Allozyme and 16S rRNA sequence data were used to explore the degree of population differentiation between mountain stream populations of two distinct freshwater crab species. Marked patterns of differentiation were evident among populations; those in close geographical proximity were characterized by the fixation of alternate alleles at certain loci, indicating that currently there is no gene flow among populations. Both allozyme and sequence data provide evidence for the recognition of at least five distinct evolutionary lineages with pronounced levels of genetic differentiation. Morphometric data failed to detect any distinct geographically intermediate population groupings. Our findings indicate the presence of five phylogeographical units, all worthy of conservation, three of which are evolutionarily significant. © 2003 The Linnean Society of London, Biological Journal of the Linnean Society , 2003, 78, 129–147.
Document Type: Research Article
Affiliations: 1: Department of Zoology, University of Stellenbosch, Private Bag X1, Matieland, 7602, South Africa 2: KwaZulu-Natal Nature Conservation Service, PO Box 13053, Cascades, 3203, South Africa
Publication date: 2003-01-01