Ringicula Deshayes, 1838

Helwerda, Renate A., 2015, Acteonidae, Bullinidae and Ringiculidae (Gastropoda: Heterobranchia) from the Plio-Pleistocene of the Philippines, Zootaxa 3990 (2), pp. 197-220 : 209

Genus Ringicula Deshayes, 1838

Remarks. The apertural characters of Ringicula shells change severely during shell growth. The shell develops callused lips, which start out thin and smooth, but end up bearing nodules, lamellae, folds and/or crenulations. Thus, specimens within a single species can show considerable differences in the strength of these characters, depending on the developmental stage of the shell. Additionally, repaired breaks are quite common in Ringicula shells. Specimens with repaired breaks tend to deviate from whole specimens in having fewer whorls and an aberrant size and height/width-ratio. These aspects impede species identification when only limited material is available.

Type species. Auricula ringens Lamarck, 1804 (by subsequent designation of Adams (1847)); Eocene, Paris Basin, France.