ThePowelliphanta gilliesi — traversi — hochstetteri — rossiana — lignaria — superbaring species (Mollusca: Pulmonata)

Abstract

An alternative classification of the New Zealand rhytidid genus Powelliphanta O'Connor, 1945 is presented. P. gilliesi (Smith, 1880) and P. hochstetteri (Pfeiffer, 1862) are recognised as species, and the following subspecies are recognised within hochstetteri: h. superba (Powell, 1930); h. lignaria (Hutton, 1880); h. rossiana (Powell, 1930); h. fiordlandica (Climo, 1971). A model is explained which suggests that all described species and subspecies of Powelliphanta are part of a complex ring species. This developed as a result of glacial disjunction of South Island populations and hybridisation across a Cook Strait land bridge formed during the last Pleistocene glaciation.