A new species of Parennea Pilsbry (Gastropoda: Streptaxidae) from the West Usambara mountains, Tanzania

Ptychotrema (Parennea) mazumbaiense is described as a new species from Mazumbai Forest, in the West Usambara mountains, north-east Tanzania. It was collected from forest-floor leaf-litter in sub-montane forest habitat at an altitude of 1600–1700 m above sea level. It is the second species of Parennea reported from Tanzania and is characterised by its strong ribbing, the form of the sinus between the angular and palatal denticles, and the presence of a deeply set, elongated spiral palatal lamella which is not visible when viewed from shell aperture.