Ringicula

Helwerda, Renate A., 2015, Acteonidae, Bullinidae and Ringiculidae (Gastropoda: Heterobranchia) from the Plio-Pleistocene of the Philippines, Zootaxa 3990 (2), pp. 197-220 : 214

publication ID	https://doi.org/ 10.11646/zootaxa.3990.2.2
publication LSID	lsid:zoobank.org:pub:BDF1BC11-4848-4858-99DC-0336A5FBEE2B
DOI	https://doi.org/10.5281/zenodo.6116545
persistent identifier	https://treatment.plazi.org/id/03FA878C-9501-FE5B-FF26-E1DE02A6CCC2
treatment provided by	Plazi
scientific name	Ringicula
status

Treatment

Ringicula View in CoL spec 3

( Figure 33 View FIGURE 29 – 33. 29 )

Material. Tiep2 (1) RGM 961.834.

Characterization. Shell small; H 2.15 mm, W 1.40 mm; protoconch slightly elevated, 1.2 whorl, DP 0.23 mm; nucleus small, DN 0.10 mm; teleoconch with distinct subsutural ridge and groove; additional sculpture of 16 spiral grooves on the body whorl; outer lip very thick with swollen lower half; parietal callus with lamella; columella with two folds; lower fold bears two knobs.

Remarks. This specimen is similar to Ringicula opima nov. spec., but its spire is smaller and it has fewer whorls. The thought arose that this specimen is therefore a deviant specimen of this species, with a teratologically small size. However, its apertural callus is well developed, but it does not extend as far onto the base as in Ringicula opima nov. spec.. It also bears two knobs on the lower fold of the columella and its outer lip is only slightly projected beyond the columella. The rest of the apertural characters were obscured by sediment, but they were revealed by making a 3D reconstruction of a CT-scan of this shell. This shows that the columellar folds are also shaped differently. All in all, this specimen differs from Ringicula opima nov. spec. in so many characters, that it is treated separately here.