Bivalvia - Pholadomyida - Megadesmidae
Parent taxon: Edmondiacea according to N. J. Morris et al. 1991
See also Bouchet et al. 2010, Nevesskaja 2009 and Vokes 1980
Sister taxa: Edmondiidae, Pachydomidae
Subtaxa: Astartila Astartilinae Carnauba Crassiconcha Ferrazia Huabiella Jacquesia Megadesminae Megadesmus Plesiocyprellinae Plesiocyprinellinae Pleurikodonta Pyramus Romaniamya Unklesbayella
Type: Megadesmus
Ecology: facultatively mobile infaunal suspension feeder
Distribution:
• Triassic of Romania (1 collection), the Russian Federation (6)
• Permian of Afghanistan (1), Australia (113), Brazil (32), China (6), Greenland (1), India (5), Japan (1), Namibia (1), Nepal (3), New Zealand (6), Pakistan (1), the Russian Federation (17), South Africa (2), Venezuela (1)
• Namurian of Australia (4)
• Carboniferous to Permian of the Russian Federation (1)
• Carboniferous of Argentina (2), Australia (1), Brazil (1), United States (6: New Mexico, Ohio, West Virginia)
Total: 212 collections including 314 occurrences