Edmondia sp.

Catalog Number: CG-0039

The genus Edmondia was first described by de Koninck in 1841. The book is Description des animaux fossiles qui se trouvent dans le terrain carbonifére de Belgique, written in the French language. The genus occurs from 252.3 to 457.5 million years ago. It died out during the Permian–Triassic extinction event. This specimen only measures 3mm wide and 1.5mm long. It is also complete, with both shell halves surviving and attached. The specimen sat on a piece of black to dark grey marine shale. This shale layer sits above the Brush Creek limestone layer.

I originally choose P. oweni as the species as it is the common Brush Creek species listed in the book Bulletin 67: Pennsylvanian Marine Bivalvia and Rostroconchia of Ohio from the State of Ohio Geological Society. The genus Palaeoneilo was first described by Hall & Whitfield in 1869.

I also considered the genus Phestia Chernyshev 1951. However, neither side tapers off to a sharper point that the other. Nor does the umbo come to a sharp point as it does in reference plates for the species. Phestia is found from 412.3 to 252.3 million years ago. Specimens exist in Pennsylvania, however the morphology does not line up.

Edmondia sp. — Illustration: De Koninck, Laurent Guillaume, 1841, Description des animaux fossiles qui se trouvent dans le terrain carbonifère de Belgique.

References

Hoare, R.D., 1979, Bulletin 67: Pennsylvanian Marine Bivalvia and Rostroconchia of Ohio, State of Ohio Div. of Geological Survey
Feldmann, R.M., 1996, Bulletin 70: Fossils of Ohio, State of Ohio Div. of Geological Survey
De Koninck, Laurent Guillaume, 1841, Description des animaux fossiles qui se trouvent dans le terrain carbonifère de Belgique, Plate I, Page 42 [PDF]
Permian–Triassic extinction event on Wikipedia