I Need Help To Identify An Otariid Carpal Bone

[lore apple]

Hi.

I need some help to identify a carpal bone. The label says it is a carpal bone, though I don't really know.

It belongs to an otariid, maybe Thalassoleon mexicanus, from the Almejas Formation of Cedros Island, Baja California.

I need to know if it's a triquetral, pisiform, trapezium, trapezoid, capitate or hamate bone.

I'm so confused

I hope the pictures help, but if you need better ones let me know.

Thank you.

[RichW9090]

It appears that there is only a single articular facet, which limits the possibilities, I think, to a pisiform or a sesamoid.

[Boesse]

Hello Lore apple,

That indeed looks to be an unciform (aka hamate). Never seen an otariid unciform before, but it's not too far off from dusignathine walrus unciforms. I work on fossil pinnipeds from California - are you at UABCS or something?

Bobby

[lore apple]

Thank you very much Rich and Bobby. Both of your opinions helped me a lot.

Bobby, I'm also working on fossil pinnipeds from California. Otarids to be precise. But not at the UABCS but the UABC which is located in Ensenada, Baja California. Sorry for answering this late but I've been trying to identify my specimens :S