Changhsingian (late permian) brachiopod palaeobiogeography

Detailed statistics show that 141 brachiopod genera from 50 families are known from the Changhsingian, occuring at 21 stations. Calculation of Jaccard's coefficient and Simpson's coefficient between all pairs of stations, together with analyses of faunal compositions, reveals the existence of five marine provinces. The extent of the Palaeo-Equatorial Region apparently expanded, probably owing to global warming, during the later Permian. No Boreal-type brachiopod faunas are reliably known from the Changhsingian. Gondwanan-type brachiopod faunas of the Changhsingian seem to be known only from New Zealand, suggesting that the Austrazean Province was still present. Changhsingian brachiopods of the Austrazean Province consist mainly of species of Aperispirifer, Spiriferella, Tomiopsis and Notospirifer. The southern Kitakami fauna of Northeast Japan, consisting of Megousia, Tschernyschewia, Orthothrix, Paramarginifera and Eolyttonia, may be the unique vestige of the Sino-Mongolian Province. The Cathaysian Province is composed of the Yangtze Block, Qiangtang Terrane, Qaidam Basin, Lhasa Terrane, Maizuru Belt of southwest Japan, Thailand and Vietnam. This province is characterized by Peltichia, Perigeyerella and Paryphella. The western Tethyan Province, along the west coast of Tethys, is closely linked with the Cathaysian Province. Its most distinctive genus is Comelicania. The Himalayan Province is of predominantly Gondwanan aspect, with some Tethyan components. The Sino-Mongolian Province, typified by the Kitakami faunas, occupied a position between Tethys and the Boreal Realm.