Rhynchonellata - Orthida - Plaesiomyidae
Parent taxon: Plaesiomyidae according to M. Liljeroth et al. 2017
See also Mitchell 1977, Williams et al. 2000 and Zuykov et al. 2008
Sister taxa: Bokotorthis, Evenkininae, Metorthinae
Subtaxa: Austinella Campylorthis Chaulistomella Dinorthis Madiorthis Multicostella Plaesiomys Retrorsirostra Valcourea
Ecology: stationary epifaunal suspension feeder
Distribution:
• Silurian of Sweden (6 collections)
• Uhaku of the Russian Federation (1)
• Whiterockian of United States (12: Nevada)
• Chazyan of Canada (19: Northwest Territories, Ontario, Quebec), United States (57: New York, Tennessee, Virginia)
• Arenig of Bolivia (3), Canada (1: New Brunswick), China (2)
• Ordovician to Silurian of United States (1: California)
• Ordovician of Argentina (5), Australia (19), Belarus (2), Bolivia (5), Canada (127: British Columbia, Manitoba, Northwest Territories, Nunavut, Nunvait, Ontario, Quebec), China (13), Estonia (20), France (1), Ireland (5), Kazakhstan (23), Myanmar (1), Norway (4), Peru (1), Poland (1), the Russian Federation (21), the United Kingdom (53), United States (351: Alaska, California, Colorado, Georgia, Idaho, Illinois, Illinois, Iowa, Indiana, Iowa, Kentucky, Michigan, Minnesota, Missouri, Nevada, New Mexico, New York, Ohio, Oklahoma, Pennsylvania, Tennessee, Texas, Virginia, Wisconsin, Wyoming)
• Ibexian of United States (1: Nevada)
Total: 755 collections including 957 occurrences