Stomatella, Lamarck, 1816

Hansen, Thomas, 2019, Gastropods from the Cretaceous-Palaeogene boundary in Denmark, Zootaxa 4654 (1), pp. 1-196 : 72

Stomatella sp.

Figs 22 B–C

Material. Specimen MGUH 33110 is an external mould of the apex.

Occurrence. The lower Danian ‘dead layer’ at Vokslev Quarry, Northern Jutland.

Description. Low-spired shell with apex relatively close to posterior margin. Protoconch moderately highspired with 1 2/3 smooth, convex whorls and a moderately wide initial chamber. The width is 0.3 mm. Transition to teleoconch marked by slight lessening in whorl convexity and a beginning of growth lines.

Teleoconch whorls convex, relatively high, with well marked suture line. Whorl angle close to 110˚. Whorl width increasing moderately fast. Transition to base seemingly sharp. Teleoconch surface smooth with weak, prosocyrt growth lines.

Measurements. MGUH 33110 is 1.4 mm wide and approximately 0.4 mm high, consisting of 1 ½ teleoconch whorls and protoconch.

Remarks. The taxon is clearly distinguished from the Danish middle Danian Stomatella sp. sensu Lauridsen & Schnetler (2014) by the marked suture line and convex, well defined whorls.

Figures

FIGURE 22. A. Phorcus sp., Silicone cast of MGUH 33109. Exposed width 2.2 mm. B–C. Stomatella sp., External mould of MGUH 33110. Figure B has been colour inverted and mirrored to show it in positive. Width 1.5 mm. D–F. Solariella sp. D–E. Silicone cast of MGUH 33111. Width 6.2 mm. F. Silicone cast of aperture of MGUH 33112. Width 5.95 mm. G–I. Skenea sp. G–H. Inner mould of MGUH 33113. Width 5.2 mm. I. Inner mould of MGUH 33114. Width 10.2 mm. J–K. Leucorhynchia sp., Silicone cast of MGUH 33115. Width 2.4 mm. L–N. Tectus? indecorus n. sp., L. Umbilical view of inner mould of paratype ØSM.10042-327-b. Width 19.7 mm. M–N. Silicone cast of holotype MGUH 33116. Width 1.7 mm. O–P. Homalopoma sp., Silicone cast and inner mould of MGUH 33117. Width 9.6, 6.9 mm respectively. Q. Calliomphalus (Calliomphalus) sp., Silicone cast of MGUH 33118. Width 3.1 mm. R–U. Arene jakobseni n. sp. R–T. Silicone cast of holotype MGUH 33119. Width 8.6 mm. U. Silicone cast of paratype MGUH 33120. Width of aperture 4.8 mm.