Gastornis Eggshell

[Othniel C. Marsh]

The item shown below is supposed to be a fragment of Gastornis eggshell, but the texture of the fragment does not look like that of any other fossil eggshell I have ever seen, avian or otherwise.

 

 

Thanks in advance for any guidance
Othniel

[Kikokuryu]

I think it's just covered up a bit with matrix or a lot of detail is worn away. It's a very small piece.

 

You want a picture of the cross section and the thickness of the shell.

 

There's 2 morphologies of eggshells from the Ypresian deposits there, Ornitholithus arcuatus that's associated with Gastornis sp. that has a 2mm thickness, while Ornitholithus biroi which has a 1mm thickness.

[Othniel C. Marsh]

6 hours ago, Kikokuryu said:

I think it's just covered up a bit with matrix or a lot of detail is worn away. It's a very small piece.

 

Thanks Kikokuryu, but I have to ask, aren't ootaxa created only when eggs are involved? If an egg(shell) was found in association with a Gastornis of some description, wouldn't the oospecies be discarded?

[Troodon]

To address your oospecies question,  all I can add to this discussion is this study.  Eggshells were 2mm thick.

 

Conclusions of study:

"This new study of the bird eggshells from the Early Tertiary of southern France permits us to associate the fossils eggs with Gastornis, as well as to propose a body mass estimate for the female of Gastornis, which is totally in accordance with the estimates independently obtained for this Early Tertiary giant ground bird"

 

 

ANGST, D., BUFFETAUT, E., LÉCUYER, C., AMIOT, R., SMEKTALA, F., GINER, S., . . . MARTINEZ, A. (2015). Fossil avian eggs from the Palaeogene of southern France: New size estimates and a possible taxonomic identification of the egg-layer. Geological Magazine,152(1), 70-79. doi:10.1017/S0016756814000077