Permian Brachiopods from Axel Heiberg Island, Canada, and an Index of Sampling Efficiency

• Published in: Journal of paleontology 1971-05, Vol.45 (3), p.502-521
• Main Authors: Stehli, Francis G., Grant, Richard E.
• Format: Article
• Language: English
• Subjects: Beak; Boreal age; Cold water; Fauna; Fossils; Genera; Geology; Heart valves; Septum; Southern hemisphere
• ISSN: 0022-3360; 1937-2337

A small collection of brachiopods from 81°N provides another control point for comparison of the Boreal with the Tethyan faunal realm of the Permian; it contains a fairly complete representation of the typically Arctic suite of brachiopods now known from many circumpolar localities. Its low diversity reflects lack of the endemic forms that make up a large percentage of Tethyan faunas. Experience shows that 16 Cosmopolitan Dominant families can be expected at most Permian localities containing brachiopods. An index of sampling Efficiency is based upon the ratio of those families actually found to the 16 that can be expected. The index for Svartevaeg, Axel Heiberg Island, is 0.81, a high index for rapid reconnaissance collecting. Application of the index to other localities shows that lack of endemism has resulted in more complete sampling of Boreal faunas than of those south of 30°N. Systematic comparison of the fauna reveals representatives of Beecheria and Glossothyropsis for the first time in the Arctic Permian; Crurithyris aquilonia and Paeckelmannella calignea are new species. The fauna is considered Guadalupe in age (about equivalent to the Word Formation), roughly correlative with the fauna of central East Greenland, and the "Svalbardian" of Svalbard.