Abstract
Evolutionary relationships in the widely distributed velvet worm P eripatopsis balfouri sensu lato species complex were examined using DNA sequence data, gross and SEM morphology. Sequence data were generated for the COI mt DNA and the 18S rRNA loci and analysed using a B ayesian inference approach, maximum likelihood and maximum parsimony. Phylogenetic analyses of the combined DNA sequence data revealed that P eripatopsis clavigera specimens from the southern C ape (clade 1) was sister to P . balfouri sensu lato specimens from the C ederberg M ountains (clade 2). Within the main P . balfouri sensu lato species complex, three addition clades could be discerned (clades 3, 4 and 5). The obligatory troglobitic species P eripatopsis alba was equidistant between the C ape P eninsula and adjacent interior (clade 3) and the two B oland and H ottentots H olland M ountains (clades 4 and 5). On the C ape P eninsula, P . stelliporata specimens nested among the sympatric P . balfouri sensu lato specimens. The C ape P eninsula specimens were sister to specimens from Jonkershoek site 1, K ogelberg and S imonsberg. Two B oland clades were retrieved, comprising D u T oit's K loof, B ain's K loof and M itchell's P ass and sister (in clade 4) to specimens from the B oland and adjacent H ottentots H olland M ountains in clade 5. These results revealed complex biogeographic patterning in the P . balfouri sensu lato species complex. The presence of sympatric, yet genetically discrete species pairs at six of the sample localities ( D u T oit's K loof, S imonsberg, J onkershoek sites 1 and 2, K ogelberg and L androskop) suggests that there is reproductive isolation between the lineages. Divergence time estimations suggest a M iocene/ P liocene/ P leistocene cladogenesis. A taxonomic revision of the P . balfouri sensu lato species complex was undertaken to stabilize the taxonomy. P . clavigera is monophyletic and retained for the southern C ape specimens, P . balfouri sensu stricto is now confined to the C ape P eninsula and adjacent interior, while P . stelliporata is regarded as a junior synonym of the latter taxon, P . alba is endemic to the W ynberg C ave systems on the C ape P eninsula. Three novel species ( P eripatopsis cederbergiensis, sp. n., P eripatopsis bolandi sp. n. and P eripatopsis purpureus, sp. n.) are described.