A new pteraspid (Agnatha, Heterostraci) from the Lower Devonian Drake Bay Formation, Prince of Wales Island, Nunavut, Arctic Canada, and comments on environmental preferences of pteraspids

ABSTRACT

A new genus and species of pteraspid heterostracan, Mitraspis cracens, gen. et sp. nov., is described from the Early Devonian (Lochkovian) Drake Bay Formation of Prince of Wales Island, Nunavut, Arctic Canada, where it is associated with a rich shallow marine invertebrate fauna. This pteraspid is most closely related to Canadapteraspis based on the arrangement of its sensory canal system, but shows an elongated morphology most similar to that seen in Rhinopteraspis and Althaspis. The unusually elongated rostrum and dorsal spine suggests adaptation for rapid movement. Analysis of the environments in which pteraspids are preserved in the Early Devonian of the Canadian Arctic shows that the same species may have inhabited a variety of environments ranging from deltaic to shallow marine.

http://zoobank.org/urn:lsid:zoobank.org:pub:4FE00E0DD215-4328-97AB-854F204E4122

Citation for this article: Elliott, D. K., H.-P. Schultze, and A. Blieck. 2015. A new pteraspid (Agnatha, Heterostraci) from the Lower Devonian Drake Bay Formation, Prince of Wales Island, Nunavut, Arctic Canada, and comments on environmental preferences of pteraspids. Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2015.1005098.

ACKNOWLEDGMENTS

D.K.E. thanks M. Reich and T. Stegemann for making the collection available and assisting him during his visit to the university museum in Göttingen. H.-P.S. thanks the DFG (German Science Foundation) for support of the expedition in 1975 and R. Thorsteinsson (deceased), at the time head of the Arctic Division of the Geological Survey of Canada, for guidance during the expedition. Figure 5 was drafted by C. Brose. This paper was improved by the helpful comments of two anonymous reviewers.