Fig. 17 in The first dsungaripterid pterosaur from the Kimmeridgian of Germany and the biomechanics of pterosaur long bones

Fig. 17. Three hypothetical step cycles in quadrupedal locomotion of DFMMh/FV 500. Lines of action of the major hip muscles shown in start of retraction phase (A), intermediate (B), and start of protraction phase (C). Note vertical position of the pelvis and relatively good mechanical advantage of the muscle lever arms through all stages.