For example, the wide zygapophyses of the vertebrae allow for a high degree of lateral flexibility, and Procynosuchus may have used anguilliform locomotion, or eel-like undulation, to swim through the water.

The long haemal arches would have given the tail a large lateral surface area for greater propulsion through the water.

Ridges on the femur are an indication of strong flexor muscles that could have stabilized the leg during limb-driven swimming.

Strong flexor muscles would have pulled the lower leg back with the femur, providing the powerful backward thrust that is needed to swim.

Under the International Code of Zoological Nomenclature (ICZN), these two names take precedence over Procynosuchus because they were erected earlier.