Crocodiles and some dinosaurs have a second set of ribs between the sternum and pelvis called [gastralia](https://en.wikipedia.org/wiki/Gastralium). Where are the gastralia attached to the rest of the skeleton?
They are not attached to the vertebrae or ribs like other bones in the body, but instead are embedded within the abdominal muscles and attached to the sternum and pubis through midventral ligament.