Natica, Scopoli, 1777

Hansen, Thomas, 2019, Gastropods from the Cretaceous-Palaeogene boundary in Denmark, Zootaxa 4654 (1), pp. 1-196 : 93-94

Natica sp. B

Figs 25 H–I

2014 Natica sp. Hansen & Surlyk: 339, tab. 3.

Material. MGUH 33157 and ØSM.10042-329-b–c. An additional four fragmentary moulds with the unofficial sample numbers SH.17, SR.749.B, SR.1090.B–C and SR.1118 are deposited at the Natural History Museum of Denmark.

Occurrence. Top upper Maastrichtian Højerup Member, Tor Formation at Rødvig, Højerup and Holtug, Stevns Klint.

Description. Protoconch low, consisting of two smooth and slowly widening whorls. Transition to teleoconch marked by distinct growth stop.

Teleoconch seemingly sub-globose with fast expanding and in profile evenly rounded whorls lacking adapical ramp. Whorls abutting.

Measurements. Most complete specimen, MGUH 33157, is at least 2.3 mm wide, consisting of slightly over three whorls.

Remarks. The taxon resembles Natica sp. A described above, but differs by a more rounded aperture and the absence of a shoulder ramp. As the material is very limited and fragmentary, completely lacking a preserved aperture, it is not possible to completely verify whether the two taxa are conspecific or not.

Figures

FIGURE 25. A–G. Natica sp. A. A–B. Silicone cast of MGUH 33154. Width 7.9 mm. C–D. Silicone cast of MGUH 33155. Width 1.4 mm. E–G. Silicone cast of MGUH 33156. Width 2.1 mm. H–I. Natica sp. B. Silicone cast of MGUH 33157. Width 2.3 mm. J–N. Polinices sp. A. J–L. Silicone cast of MGUH 33158. Width 3.0 mm. M–N. Silicone cast of MGUH 33159. Width 5.2 mm. O–P. Polinices? sp. B. Silicone cast of MGUH 33160. Width 5.0 mm. Q–R. Rissoina? sp., Silicone cast of MGUH 33161. Width 0.6 mm. S–U. Zebinella selandica n. sp., Silicone cast of holotype MGUH 33162. Width 0.8 mm. Width of protoconch 0.55 mm. V. Alvania sp. A. Silicone cast of MGUH 33163. Width 1.2 mm.