Gastropods from the Cretaceous-Palaeogene boundary in Denmark
Author
Hansen, Thomas
text
Zootaxa
2019
2019-08-12
4654
1
1
196
journal article
26049
10.11646/zootaxa.4654.1.1
9ce1d103-9234-4fbe-9544-f1c294bb8783
1175-5326
3365803
CFD82CC0-3110-472E-972B-7ADC0C523A04
Dzikella
? sp.
Fig. 24L
Material.
Specimen
MGUH
33146 is a fragmentary teleoconch mould.
Occurrence.
Lithified top of the Højerup Member of the Maastrichtian Tor Formation north of Kulsti Rende.
Description.
Teleoconch broadly coeloconoid with weakly convex, nearly flattened whorls with a strongly angular abapical keel and separated by somewhat grooved sutures. Whorl height approximating 2/5 the width. Base weakly convex. Columella smooth with no columellar fold. Whorls subrectangular in cross section.
Early teleoconch sculpture consisting of 12 to 18 coarse transverse ribs and fine spiral lirae. Transverse ribs reaching from adapical two spiral lirae and abapically to keel. Later teleoconch whorls smooth except for two weak adapical spiral lirae and two similarly weak abapical spiral lirae located slightly adapically of keel. Growth lines strongly prosocline, slightly prosocyrt.
Measurements.
Specimen
MGUH
33146 is
7.2 mm
high and 6.0 mm wide, consisting of 6 ½ teleoconch whorls.
Remarks.
The Danish taxon resembles the late Maastrichtian
D. chukinensis
Kaim, Beisel & Kurushin, 2004
from Western Sibiria, but differs by the concave sided spire, the more flattened whorls with the abapically located keel and by a less convex base.