Modiolus
Species
Modiolus isonemus (Meek, 1877)
Has fine regularly spaced concentric ribs, less arched
Occurrence: Twin Creek, Arapien
Reference: Imlay, 1964
Modiolus subimbricatus (Meek, 1873)
Has coarser imbricate ribs, more highly arched
Occurrence: Carmel Formation; Sliderock, Rich, and Watton Canyon Members of Twin Creek Limestone
Reference: Imlay, 1964; Imlay, 1967
Modiolus subimbricatus
Photograph from Imlay, 1964
Modiolus (Musculus) sp.
Occurrence: Rich Member of Twin Creek Limestone
Reference: Imlay, 1967
Modiolus (Musculus) sp.
Photograph from Imlay, 1967
