23-13 A Rare Hadrosaur (Dinosauria, Ornithischia) Chevron from the Late Cretaceous (upper Campanian) Coon Creek Formation of West Tennessee

Session: Paleontology of North America (Posters)

Presenting Author:

Authors:

Abstract:

Dinosaur remains are exceedingly rare in upper Cretaceous strata in Tennessee. Previous reports describe disarticulate remains comprised mostly of partial bones, isolated teeth, and vertebrae. Here, we report a median chevron of a large-bodied hadrosaur (Dinosauria, Ornithischia) from the Sawmill Site locality in Decatur County, Tennessee. The chevron is nearly complete, measuring 276 mm. It preserves the entirety of the haemal arch and all but the distalmost section of the ventral spine. It bears an unroofed oval-shaped haemal canal measuring 86 mm by 25 mm and a spine measuring 188 mm long. The chevron originates from the Coon Creek Formation (Late Campanian), a world renowned lagerstätte known for exceptional molluscan preservation at the lower facies of its type section. This specimen was found in the upper facies within the Nostoceras hyatti ammonite zone. This specimen represents a rare terrestrial record from the marine strata of the Mississippi Embayment of the Gulf Coastal Plain of the United States. It further constitutes the fourth dinosaur record in Tennessee and the second largest dinosaur bone known from the state.

Geological Society of America Abstracts with Programs. Vol. 58, No. 1, 2026

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