Pelomedusa barbata Petzold & Vargas-Ramírez & Kehlmaier & Vamberger & Branch & Preez & Hofmeyr & Meyer & Schleicher & Široký & Fritz 2014, sp. nov

Pelomedusa barbata sp. nov. Diagnosis: Medium-sized, light-coloured helmeted terrapins with a known maximum straight carapacial length of 21.6 cm (Gasperetti et al. 1993). Pectorals with narrow to broad midseam contact. Two small temporal scales (rarely only one large scale) on each side of head. Two or three large to very large barbels under chin. In adults, carapace light coloured, plastron entirely yellow. Pelomedusa barbata differs from all other Pelomedusa species by a gap instead of adenine (A), cytosine (C) or thymine (T) at position 122 and by the presence of guanine (G) instead of adenine (A) at position 330 of the 360-bp-long reference alignment of the 12S rRNA gene (Supporting Information). Holotype: Museum für Tierkunde, Senckenberg Dresden (MTD D 24637, male, Zinjibar, Abyan, Yemen, N13°7.75 E45°22.81; leg. W. Wranik, 3 June 1985; Fig. 3 top). Description of the holotype: Straight carapacial length 12.3 cm, plastral length 10.4 cm. Pectoral scutes triangular and in narrow contact at the midline. Temporal scale divided on left side, undivided on right side of head. Two large barbels below chin. Carapace horn-coloured, plastron yellow with sparse grey mottling. Dorsal side of soft parts grey to horn-coloured, ventral side cream-coloured with a yellow tinge. Tail long. Paratypes: Muséum d’Histoire Naturelle Genève (MNHG 2310.062, adult male, Al Sukhna, Yemen; MNHG 2455.073 – 075, adult male and two juveniles, Wadi Warazan, Lahij, Yemen); Museum für Tierkunde, Senckenberg Dresden (MTD D 24638, adult female, Lahij, Yemen); The Natural History Museum, London (BMNH 1985.1475, mummified adult, Al Kadan, Tihama, Al Hudaydah, Yemen; BMNH 1985.1478 – 1479, adult male and female, Amanat Al Asimah, Sana’a Area, Yemen); Zoologisches Forschungsmuseum Alexander Koenig, Bonn (ZFMK 87122, juvenile, Asir Region, Saudi Arabia). Derivatio nominis: The scientific name (Latin: bearded) refers to the large barbels beneath the chin of the new species. Distribution: Southwestern Arabian Peninsula (Saudi Arabia, Yemen; Gasperetti et al. 1993; Vargas-Ramírez et al. 2010; Wong et al. 2010). Remarks: Pelomedusa barbata corresponds to mtDNA lineage VII of Vargas-Ramírez et al. (2010). According to our analyses of mtDNA, P. barbata belongs to the northern species group of Pelomedusa and is most closely related to P. somalica (Fig. 1). Gasperetti et al. (1993) mention that they have studied helmeted terrapins from southwestern Arabia that “more or less encompass all of the plastral variations” described for Pelomedusa and “all of the colour descriptions, from the lightest tan colour to almost black”. However, their figures show only terrapins with pectoral scutes in contact, matching our observations. We never encountered dark coloured Arabian terrapins. Pelomedusa barbata is the only chelonian species endemic to the Arabian Peninsula. Due to the paucity of local freshwater habitats, P. barbata should be regarded as an endangered species.