Exploring the impact of habitat size on phylogeographic patterning in the Overberg velvet worm Peripatopsis overbergiensis (Onychophora: Peripatopsidae)

Evolutionary relationships in the velvet worm species, Peripatopsis overbergiensis, were examined in 3 forest areas in the Overberg region of South Africa to explore the impact of historical habitat fragmentation on the population genetic structure of the species. We collected 84 P. overbergiensis specimens from Grootvadersbosch, Koppie Alleen, and Marloth Nature Reserves and sequenced all these specimens for the cytochrome c oxidase subunit I (COI) locus, whereas a subset of 13 specimens were also sequenced for the 18S rRNA locus. Phylogenetic analyses of the 20 unique COI haplotypes revealed 4 genetically distinct clades, a result that is corroborated by the haplotype network. A hierarchical analysis of genetic variation was performed on the COI haplotype data within the 2 large forested areas, Grootvadersbosch and Marloth Nature Reserves, and across all 3 of the sample localities. These results revealed low haplotypic and nucleotide diversity within the largest Grootvadersbosch Natur...