Translator Disclaimer
28 February 2019 Neritoptyx hogansoni new species (Gastropoda, Mollusca) from the Upper Cretaceous Fox Hills Formation on the Dakota Isthmus, western United States
J. Mark Erickson
Author Affiliations +
Abstract

In midcontinent North America, the Fox Hills Formation (Upper Cretaceous, upper Maastrichtian) preserves the last marine faunas in the central Western Interior Seaway (WIS). Neritoptyx hogansoni new species, a small littoral snail, exhibited allometric change from smooth to corded ornament and rounded to shouldered shape during growth. Specimens preserve a zig-zag pigment pattern that changes to an axial pattern during growth. Neritoptyx hogansoni new species was preyed on by decapod crustaceans, and spent shells were occupied by pagurid crabs. Dead mollusk shells, particularly those of Crassostrea subtrigonalis (Evans and Shumard, 1857), provided a hard substrate to which they adhered on the Fox Hills tidal flats. This new neritimorph gastropod establishes a paleogeographic and chronostratigraphic proxy for intertidal conditions on the Dakota Isthmus during the lateMaastrichtian. Presence of a neritid extends the marine tropical/temperate boundary in the WIS northward to ∼44° late Maastrichtian paleolatitude. Late Maastrichtian closure of the isthmus subsequently altered marine heat transfer by interrupting northward flow of tropical currents from the Gulf Coast by as much as 1 to 1.5 million years before the Cretaceous ended.

© 2018, The Paleontological Society
J. Mark Erickson "Neritoptyx hogansoni new species (Gastropoda, Mollusca) from the Upper Cretaceous Fox Hills Formation on the Dakota Isthmus, western United States," Journal of Paleontology 93(2), 278-290, (28 February 2019). https://doi.org/10.1017/jpa.2018.82
Accepted: 12 September 2018; Published: 28 February 2019
JOURNAL ARTICLE
13 PAGES


Share
SHARE
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top