Description of a new species of Potamonautes MacLeay, 1838, from the iSimangaliso Wetland Park,South Africa

A new species of freshwater crab, Potamonautesisimangalisosp. n., is described from the western shores of False Bay, Hluhluwe, within the iSimangaliso Wetland Park, South Africa. While bearing a superficial resemblance to Potamonauteslividus, the new species has been found to be genetically distinct, diverging from the former by 7.4–7.8% in mtDNA. Potamonautesisimangaliso most closely resembles Potamonauteslividus, but is distinguished by a unique suite of carapace characters, colouration, and size. The new species also lives in close association with oxygen-poor, fresh ephemeral pans, while the habitat of Potamonauteslividus is well above the surface water line of the closest water body. An updated identification key for the Potamonautes species of South Africa is provided.