Trilobita - Proetida - Dimeropygidae
Full reference: P. E. Raymond. 1925. Some trilobites of the lower Middle Ordovician of eastern North America. Bulletin of the Museum of Comparative Zoölogy at Harvard College 67(1):1-180
Parent taxon: Dimeropygidae according to R. A. Fortey and D. L. Bruton 2013
See also Fortey and Droser 1999, Jell and Adrain 2002, Raymond 1925 and Sepkoski 2002
Sister taxa: Bearriverops, Chomatopyge, Dimeropyge, Dimeropygiella, Heckethornia, Mesotaphraspidinae, Mesotaphraspis, Pseudohystricurus, Toernquistia, Tulepyge, Toernquistina
Subtaxa: Ischyrotoma anataphra Ischyrotoma borealis Ischyrotoma eos Ischyrotoma juabensis Ischyrotoma parallela Ischyrotoma sila Ischyrotoma stubblefieldi Ischyrotoma twenhofeli Ischyrotoma wahwahensis
Type: Ischyrotoma twenhofeli
Ecology: fast-moving low-level epifaunal deposit feeder
Distribution:
• Chazyan of Canada (1: Newfoundland and Labrador collection)
• Whiterockian of Canada (1: Newfoundland and Labrador), Norway (1), United States (5: Nevada, Utah)
• Arenigian of Canada (1: Northwest Territories)
• Arenig of Greenland (1), United States (1: New York)
• Ordovician of Canada (27: Newfoundland, Newfoundland and Labrador, Nunavut, Quebec), China (1), Norway (4), the United Kingdom (1), United States (46: California, Nevada, Oklahoma, Utah)
• Tremadoc of Canada (2: Alberta)
Total: 92 collections including 100 occurrences
Specimen images are retrieved through the ePANDDA API.
Click image to enlarge. Click to access iDigBio record.