Lyrodesmatidae

Classification
Phylum: Mollusca
Class: Bivalvia
Order: Trigonioda
Family: Lyrodesmatidae Ulrich, 1894
Cincinnatian Genera: Lyrodesma
Geologic Range
Middle Ordovician – Late Ordovician
Common Paleoecology
Lyrodesmatidae is an extinct family of facultatively mobile shallow infaunal suspension feeders
Description of the Family
- Small shell
- Subtrigonal shell shape
- Rounded toward anterior
- Obliquely truncate
- Hinge plate semicircular
Published Descriptions
Treatise on Invertebrate Paleontology, Part N, Mollusca 6(1 of 3) (1969):
- Shell small, subtrigonal, rounded in front, acuminate posteriorly and commonly obliquely truncate; umbonal fold rounded or carinate; beaks small; hinge plate semicircular, with several angular, crenulated teeth radiating more or less symmetrically from beneath the beak.