Acmaea, Eschscholtz in Rathke, 1833

Hansen, Thomas, 2019, Gastropods from the Cretaceous-Palaeogene boundary in Denmark, Zootaxa 4654 (1), pp. 1-196 : 58

Acmaea ? sp.

Figs 19 D–E

Material. This taxon is represented by a single wax-cast, MGUH 33080, in the collections of the Geological Museum of Copenhagen, while the original appears lost.

Occurrence. Upper part of the Maastrichtian Tor Formation slightly north of Kulsti Rende at Stevns Klint.

Description. Large shell weakly convex, with central, apparently flattened apex and an elongated oval outline. Aperture width 77 % of length, shell height approximately 20 % of length. Surface bearing fairly strong growth lines and very fine, regular, but slightly grainy radial striation.

Measurements. Shell reaching at least 18.8 mm in length.

Remarks. The apex may be secondarily deformed on the wax cast, and the assignment to genus is thus tentative.

Figures

FIGURE 19. A–C. Acmaea selandica n. sp. A. Inner mould of holotype MGUH 33077. Length 5.9 mm. B. Paratype MGUH 33078. Length 2.6 mm. C. Internal mould of paratype MGUH 33079. Length 4.45 mm. D–E. Acmaea? sp. Wax cast of now lost specimen MGUH 33080. Length 19.7 mm. F–G. Cocculina? sp. Silicone cast of MGUH 33081. Exposed length 5.7 mm. H. Symmetrocapulus? sp., external mould MGUH 33082. Length 2.4 mm. I–K. Emarginula coralliora Lundgren, 1867. I–J. Silicone cast of MGUH 33083. Length 2.9 mm, height 1 mm. K. Inner mould of MGUH 33084. Length 7.8 mm. L–Q. Cranopsis cretacea n. sp. L–O. Silicone cast and inner mould of holotype MGUH 33085. Length 3.6 mm, width 2.6 mm. P–Q. Silicone cast and inner mould of paratype MGUH 33086. Length 2.1 mm. R–S. Palaeoloxotoma sp., Silicone cast of MGUH 33087. Length 17.2 mm.