Acteonidae, Bullinidae and Ringiculidae (Gastropoda: Heterobranchia) from the Plio-Pleistocene of the Philippines Author Helwerda, Renate A. text Zootaxa 2015 3990 2 197 220 journal article 39813 10.11646/zootaxa.3990.2.2 1740ec81-c55e-44ce-9a6d-cd62acd5d898 1175-5326 242947 BDF1BC11-4848-4858-99DC-0336A5FBEE2B 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 .