Shells And Sand Dollars From Yazoo County, Ms (Moodys Branch Formation, Late Eocene)

[verydeadthings]

Hi everyone, I went on a day trip to central Mississippi about a week ago. I found some nice bivalves, gastropods, and sand dollars. Most of the material was found in situ in a sandy clay. There were abundant shells and sand dollars in the stream bed, unfortunately, the sand dollars were very fragile and I didn't have much luck getting them out without breakage. My favorite sand dollar was found as float, much more lithified than the in situ material, so I'm not sure about the age. Here it is:

I found one vertebrate bone. Any ideas on what it could be? I heard basilosaurus bones have been found in the area, but I'm certainly no expert. All the other fossils indicate a marine environment.

I managed to dig out some oyster shells that were cemented together:

Another oyster:

Here's a sand dollar found in situ that I didn't completely smash to pieces:

I will be adding the last few pictures momentarily.

[verydeadthings]

I found quite a few of these bivalves, they look like Venericardia to me but I don't know if that genus goes back to the Eocene:

A second sand dollar found in the more heavily lithified float:

Unknown bivalve:

Small bivalves:

Finally, I stopped by the type locality of the Byram Formation on the Pearl River at Byram on the way back quickly, picked up this coral from the Oligocene:

Tell me what you guys think

[Foshunter]

The sand dollars look like Periachus lyelli like the one I have found in the Alabama Eocene----Tom

[Uncle Siphuncle]

agreed. i've taken p. lyelli from the moodys branch.

[jkfoam]

That first clam is a Venericardia. And yes, the genus does go back to the Eocene and the Paleocene according to Moore, Lalicker and Fischer in "Invertebrate Fossils, (1952.

The unknown clam looks like Bathytormus. I hope this helps.

Jim

[Uncle Siphuncle]

If memory serves, the whale stuff is more common in the underlying Yazoo Clay.

[MikeR]

Moodys Branch Formation is lowermost Upper Eocene basal Jackson Stage. Mollusk IDs are as follows:

Crassostrea alabamaensis (I. Lea, 1833)

Venericardia apodensata Gardner & Bowles, 1939

Bathytormus clarkensis postclarkensis (Harris, 1919)

The small bivalves are Glycymeris idonea (Conrad, 1833) although on the bottom row in the middle is a single specimen of Pitar trigoniata (I. Lea, 1833)

Edited August 13, 2013 by MikeR

[verydeadthings]

Thanks everyone for the fossil ids!