Surveys of Afrotemperate forests yields two new freshwater crabs (Decapoda: Potamonautidae: Potamonautes MacLeay, 1838) from South Africa

  • Savel R Daniels Department of Botany and Zoology, Private Bag X1, University of Stellenbosch, Matieland, 7602, South Africa
  • Aaron Barnes Department of Botany and Zoology, Private Bag X1, University of Stellenbosch, Matieland, 7602, South Africa
  • Hannes Marais Mpumalanga Tourism and Parks Agency, Aquatic Unit, Lydenburg, 1120, Mpumalanga, South Africa
  • Gavin Gouws National Research Foundation - South African Institute for Aquatic Biodiversity, Private Bag 1015, Makhanda, 6140, South Africa
Keywords: Aquatic biodiversity, Decapoda, evolutionary relationships, novel lineages


Sampling of remote inland aquatic habitats in South Africa has constantly been yielding novel endemic freshwater crab species (Potamonautes MacLeay,1838). During the present study, we report on the discovery and description of two new freshwater crab species (Potamonautes baziya sp. nov., and P. mariepskoppie sp. nov.) from Afrotemperate forested mountain regions in the Eastern Cape and Mpumalanga provinces of South Africa, respectively. Phylogenetic evidence derived from DNA sequence data of three partial mitochondrial loci (12S rRNA, 16S rRNA and cytochrome oxidase subunit one, COI) corroborates the evolutionary distinction of the two novel species. In addition, morphological and ecological data for the two new species further delineate their evolutionary distinction from congeneric sister species. A comparison of the taxonomically important gonopods 1 and 2 and carapace features among the sister species and other known freshwater crabs of South Africa was further used to provide evidence for the distinction of the two novel species. The discovery of two new species suggest that remote mountainous areas or unsampled regions in South Africa likely harbor several novel species, reiterating a call to document aquatic inland biodiversity in forested and mountainous regions of the country.


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How to Cite
Daniels, S. R., Barnes, A., Marais, H., & Gouws, G. (2021). Surveys of Afrotemperate forests yields two new freshwater crabs (Decapoda: Potamonautidae: Potamonautes MacLeay, 1838) from South Africa. European Journal of Taxonomy, 782(1), 82-107.
Research article