Proximodorsal process

The proximodorsal process is a feature of the skeleton of archosaurs.

It may be a pair of tabs or blade - shaped flanges on the pelvis, and serves as an anchor point for the attachment of leg muscles.

This process is of particular importance in the anatomy and comparative morphology of Mesozoic birds and advanced maniraptoran dinosaurs.

The three paired bones are called the ilium, the ischium, and the pubis.

In primitive birds the ischia are complex, usually with a small or even absent obturator process and a large, rectangular, proximodorsal process extending up toward the ilium.