A revision of African helmeted terrapins (Testudines: Pelomedusidae: Pelomedusa), with descriptions of six new species Author Petzold, Alice Museum of Zoology, Senckenberg Dresden, A. B. Meyer Building, 01109 Dresden, Germany Author Vargas-Ramírez, Mario Museum of Zoology, Senckenberg Dresden, A. B. Meyer Building, 01109 Dresden, Germany Author Kehlmaier, Christian Museum of Zoology, Senckenberg Dresden, A. B. Meyer Building, 01109 Dresden, Germany Author Vamberger, Melita Museum of Zoology, Senckenberg Dresden, A. B. Meyer Building, 01109 Dresden, Germany Author Branch, William R. Department of Herpetology, Port Elizabeth Museum, P. O. Box 13147, Humewood 6013, South Africa & Department of Zoology, P. O. Box 77000, Nelson Mandela Metropolitan University, Port Elizabeth 6031, South Africa Author Preez, Louis Du Unit for Environmental Science & Management, North-West University, Potchefstroom Campus, Private Bag X 6001, Potchefstroom 2520, South Africa Author Hofmeyr, Margaretha D. Chelonian Biodiversity and Conservation, Department of Biodiversity and Conservation Biology, University of the Western Cape, Private Bag X 17, Bellville 7535, South Africa Author Meyer, Leon Unit for Environmental Science & Management, North-West University, Potchefstroom Campus, Private Bag X 6001, Potchefstroom 2520, South Africa Author Schleicher, Alfred P. O. Box 30566, Windhoek, Namibia Author Široký, Pavel Department of Biology and Wildlife Diseases, Faculty of Veterinary Hygiene and Ecology, University of Veterinary and Pharmaceutical Sciences, Palackého tř. 1 / 3, 612 42 Brno, Czech Republic Author Fritz, Uwe Museum of Zoology, Senckenberg Dresden, A. B. Meyer Building, 01109 Dresden, Germany text Zootaxa 2014 2014-05-15 3795 5 523 548 journal article 5605 10.11646/zootaxa.3795.5.2 87d17125-337d-4679-bdcd-102f6b022ad2 1175-5326 4915083 9394634C-9836-4973-868B-BDEE414E4EA8 Pelomedusa olivacea (Schweigger, 1812) 1812 Emys olivacea Schweigger —Restricted type locality: Senegal ; holotype : Muséum National d’Histoire naturelle, Paris, MNHN 7971 1884 Pelomedusa gasconi Rochebrune —Restriced type locality (by neotype designation, Fritz et al. 2014 ): Dagana, Senegal ; neotype ( Fritz et al. 2014 ): Zoologisches Forschungsmuseum Alexander Koenig, Bonn, ZFMK 17076 (Fig. 6 bottom in Fritz et al. 2014 ) Diagnosis: Small to medium-sized helmeted terrapins with a known maximum straight carapacial length of 16.8 cm . Pectoral scutes triangular and either just meeting at their tips along the plastral midseam or more or less widely separated. One large undivided temporal scale on each side of head. Two small barbels under chin. Carapace and plastron light coloured. Soft parts dorsally darker than ventrally. Pelomedusa olivacea differs from all other Pelomedusa species by the presence of guanine (G) instead of adenine (A) or cytosine (C) at position 123 and by the presence of adenine (A) instead of guanine (G) at position 271 of the 360-bp-long reference alignment of the 12S rRNA gene (Supporting Information). Distribution: Genetically verified records for P. olivacea are known from Benin , Burkina Faso , Niger , Nigeria , and Senegal ( Vargas-Ramírez et al. 2010 ; Wong et al. 2010 ; Fritz et al. 2014 ). Remarks: Pelomedusa olivacea corresponds to mtDNA lineage III of Vargas-Ramírez et al. (2010) . Phylogenetically, P. olivacea belongs to the northern clade of Pelomedusa and is most closely related to P. variabilis from Ghana and the Ivory Coast ( Fig. 1 ). In both species, the pectoral scutes may be triangular with or without midseam contact. Among 21 museum specimens of P. olivacea , 18 have completely divided pectoral scutes and three have triangular pectoral scutes just meeting at the plastral midline. This matches the description for Senegalese P. olivacea given in Rochebrune (1884) . The monogenean flatworm Polystomoides nabedei Kulo, 1980 was described from helmeted terrapins from Siborototi, Togo (most likely Pelomedusa olivacea or P. variabilis ). This parasite was described as a distinct species based on morphological differences from Polystomoides chabaudi , which is known from Pelomedusa subrufa and probably P. neumanni (see respective species accounts).