Euomphalina
Geologic Range
Early Ordovician – Late Cretaceous
Common Paleoecology
Euomphalina is an extinct order of stationary, epifaunal suspension feeders
Characteristics of the Order
- Mostly discoidal shell
- Commonly contains channel presumed to be exhalant, which occupies an angulation on the outer part of the upper whorl surface
- Most organisms widely phaneromphalous
- Thick shell wall with calcite on outside and aragonite on inside
Treatise on Invertebrate Paleontology, Part I, Mollusca 1 (1960): Under Superfamily Euomphalacea
- Shell mostly discoidal; orthostrophic or hyperstrophic; commonly with channel presumed to be exhalant occupying angulation on outer part of upper whorl surface; mostly widely phaneromphalous; shell wall relatively thick, with external prismatic layer of calcite which may be pigmented and internal layer of aragonite which is lamellar but not nacreous
Holopeidae
Platyceratidae
