Fig. 7.

Shape and orientation of the shoulder girdle elements in relation to the shape of the shell (anterior view). (A) Terrestrial turtles; (B) highly aquatic freshwater turtles; (C) marine turtles. The shape of the shoulder girdle results from the calculation of discriminant traits (see Fig. 6). The extremities of the scapular prong and the acromial process are placed on a vertical line.