Acta Palaeontologica Polonica

Revision of latest Givetian-Frasnian Atrypida (Brachiopoda) from central North America

Jed Day and Paul Copper

Acta Palaeontologica Polonica 43 (2), 1998: 155-204

The brachiopod fauna of the Middle-Late Devonian cratonic carbonate platform deposits of the Iowa Basin, central North America, contains twenty species of the order Atrypida, some of which are types for widespread genera common in Middle and Late Devonian faunas. The latest Givetian-early Frasnian deposits yield a diverse fauna consisting of ten species (two new) included in Desquamatia (Independatrypa), D. (Seratrypa), Pseudoatrypa, Radiatrypa, Spinatrypa (Spinatrypa) and Spinatrypina (Exatrypa). Many of these forms occur in, or are closely similar to species known from, coeval faunas of central and western Canada. Middle Frasnian deposits of northern Iowa contain two species included in Spinatrypa (S.) and Pseudoatrypa, both of which are new. Late Frasnian strata of the Iowa Basin yield eight species included in Costatrypa, Iowatrypa, Pseudoatrypa, and Spinatrypa (Spinatrypa), some of which are widespread in other subtropical and tropical faunas of the western US and western Canada. The taxa Pseudoatrypa witzkei sp. n., Spinatrypa (S.) bunkeri sp. n., Spinatrypa (S.) thompsoni sp. n., and Spinatrypina (Exatrypa) johnsoni sp. n. are proposed. Pseudoatrypa? sp. from the very late Frasnian of southern New Mexico is also illustrated.

Key words: Brachiopoda, Atrypida, taxonomy, Givetian, Frasnian, Devonian, North America.

Jed Day [], Department of Geography-Geology, Illinois State University, Normal, IL 61790-4400, USA.Paul Copper [], Department of Earth Sciences, Laurentian University, Sudbury, Canada P3E 2C6.

This is an open-access article distributed under the terms of the Creative Commons Attribution License (for details please see, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.