Carboniferous and Permian Rugosochonetidae (Brachiopoda) from West Spitsbergen

The rugosochonetid brachiopod species Lissochonetes geinitzianus from the Kazimovian of the Nordenskioldbreen Formation, and Dyoros (Dyoros) mucronata sp. nov., Dyoros (Dyoros) spitzbergianus and Lissochonetes superba from the Artinskian to latest Permian Kapp Starostin Formation in West Spitsbergen are described and figured. Dyoros is generally restricted to the Boreal Realm, whereas Lissochonetes is mostly distributed in the Boreal Realm, but occasionally present in the Palaeoequatorial and Gondwanan Realms<br /

Cancrinella and Costatumulus (Brachiopoda) from the Permian of South Mongolia and South China : their morphology, biostratigraphy and distribution

Two brachiopod genera, Cancrinella Fredericks and Costatumulus Waterhouse, are studied from the Permian of South Mongolia and South China. Many of the specimens previously described as Cancrinella are revised and assigned to Costatumulus. The new data presented in this paper indicate that these two genera are similar to each other, but are distinguishable by different features in relation to their morphology. Several species of both genera are described here, providing critical new information on the morphology and taxonomy of Cancrinella and Costatumulus. The reported biostratigraphical information reveals that species of Cancrinella are present from the Lower Carboniferous (Tournaisian) to Middle Permian (Capitanian), whereas species of Costatumulus are mostly restricted to the Lower Permian (Sakmarian) to Upper Permian (Changhsingian). An analysis of the palaeogeographical distribution of Cancrinella and Costatumulus reveals that Cancrinella was more commonly distributed in the Northern Transitional Zone and the Boreal Realm, in contrast to Costatumulus, which tended to be more common in the Southern Transitional Zone and Gondwanan Realm.<br /