Fossil ID - Purbeck group, near Swanage, Southern UK

[FilthyMammal]

Hello!

I've found this today near Swanage, Southern England in the Purbeck group - early Cretaceous. The initial thought was turtle rib but I'm not particularly familiar with turtle anatomy, so I thought I'd run it by the group. The location has yielded crocodiles, turtles, Iguanodontian dinosaurs and some mammals. Sadly, had a break in it when freeing it from a bigger block, but recovered most of the pieces. Note that it is flat, thin, does not appear to taper or pinch along the length - not clear from the photo but it's uniformly 0.75cm thick and before the break about 8 cm in length. Note the ridge at the right side end in the image - it would flare out slightly from this point if this is the head. The portion at bottom (the side of it) has a broken edge so would be slightly broader when complete, and the same may be true of the other side which is still in matrix. 

Any help to even a genus level would be great! 

[Coco]

Hi,

 

Broken link, you must upload the photos in JPG format directly on the forum.

 

Coco

[Rockwood]

This looks like a turtle rib to me. They are fused to the neural plate of the carapace. The texture, which is usually most diagnostic, is difficult to make out in this photo however.