Paleocene Fossil Leaf and Winged Walnut Fruit - North Dakota

This is a beautiful fossil leaf ("Cocculus" flabella) and winged walnut fruit (Cyclocarya brownii) association, collected from the Sentinel Butte Formation of North Dakota. Both fossils have beautiful detail preservation.

Comes with an acrylic display stand.

The Juglandaceae (walnuts, hickories, pecans) has one of the best-documented fossil records in the Northern Hemisphere. The oldest modern genus, Cyclocarya, today restricted to China, first appears in the late Paleocene (57 ma) of North Dakota, USA. Unlike walnuts and pecans that produce edible fruits dispersed by mammals, Cyclocarya fruits are small nutlets surrounded by a prominent circular wing, and are thought to be wind- or water-dispersed. Because Cyclocarya fruits are winged, they might be assumed to be wind-disperse, but their radial symmetry does not have the aerodynamic qualities typical of wind-dispersed fruits, and may have been dispersed by water.

A paper describing these fruits in depth is linked below.

Cyclocarya brownii from the Paleocene of North Dakota, USA

"Cocculus" flabella (Leaf) & Cyclocarya brownii (Fruit)
Morton County, North Dakota
Sentinel Butte Formation
2.1" long leaf on 4 x 3.7" rock
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