Open AccessMolecular and morphometric data demonstrate the presence of cryptic lineages among freshwater crabs (Decapoda: Potamonautidae: Potamonautes) from the Drakensberg Mountains, South Africa
Author(s) -
DANIELS SAVEL R.,
GOUWS GAVIN,
STEWART BARBARA A.,
COKE MICHAEL
Publication year - 2003
Publication title -
biological journal of the linnean society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.906
H-Index - 112
eISSN - 1095-8312
pISSN - 0024-4066
DOI - 10.1046/j.1095-8312.2003.00143.x
Subject(s) - biology , species complex , freshwater crab , gene flow , phylogeography , decapoda , taxon , population , ecology , evolutionary biology , zoology , phylogenetics , genetic variation , crustacean , phylogenetic tree , gene , genetics , demography , sociology
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.