Mind the gaps : investigating the cause of the current range disjunction in the Cape Platanna, Xenopus gilli (Anura: Pipidae)
Date
2013
Journal Title
Journal ISSN
Volume Title
Publisher
PeerJ
Abstract
Low-lying areas of the Cape at Africa’s south-westernmost tip have undergone dramatic marine-remodelling, with regular changes in sea-level following glacial cycles. Species for which marine barriers are impenetrable underwent concomitant radical distribution changes which may account for current range disjunctions. The Cape platanna, Xenopus gilli, is a frog distributed in only three disjunt areas within low-lying regions of the southwestern Cape. We determined the relationship between frogs from these three disjunct areas, by using a combination of morphometric analysis and mtDNA (ND2 and 16S fragments) sequences of 130 frogs from eight ponds. Coalescent analyses on molecular data dated the divergence in two major clades to around 4.6 Mya, a period during which major uplifting on the eastern side of the subcontinent caused climate changes throughout southern Africa. Principal components analysis showed significant morphometric differences between each clade on head and limb measurements. Consistent differences in ventral colouration and patterning were also observed. We report on increased levels of hybridisation with X. laevis throughout the range of X. gilli, which reaches at least 27% hybrids in some ponds. Urgent conservation actions are required to control habitat loss from alien invasive vegetation, and prevent introgression with the domestic-exotic, X. laevis.
Description
CITATION: Fogell, D. J., Tolley, K. A. & Measey, G. J. 2013. Mind the gaps : investigating the cause of the current range disjunction in the Cape Platanna, Xenopus gilli (Anura: Pipidae). PeerJ, 1:e166, doi:10.7717/peerj.166.
The original publication is available at https://peerj.com
The original publication is available at https://peerj.com
Keywords
Xenopus gilli, Cape Platanna, Frogs -- South Africa, Biogeography
Citation
Fogell, D. J., Tolley, K. A. & Measey, G. J. 2013. Mind the gaps : investigating the cause of the current range disjunction in the Cape Platanna, Xenopus gilli (Anura: Pipidae). PeerJ, 1:e166, doi:10.7717/peerj.166.