3D CT Anatomy and Morphology of the Appendicular Skeleton of European Pond Turtle (Emys orbicularis)

Turtles have special anatomical features due to their shell and the enclosure of their internal organs. One of the important differences between the anatomy of this group of reptiles and others is the skeletal structure. The European pond turtle (Emys orbicularis) is a species within the Emylidae family, inhabiting regions spanning Europe, Africa and Asia.

This study has been designed to assess the anatomical features of the appendicular skeletal system in this species and draw comparisons with other turtle species.

Computed tomography (CT) Scan Machine and Micro CT Scan Machine were used for this study. Gross anatomical studies were performed on prepared bones using the method of using insects.

The carpal region consists of 10 bones (5 proximal and 5 distal), whereas the tarsal region features a fused Astragalus and four distal bones, both following a 2.3.3.3.2 phalangeal formula. Significant sexual dimorphism is limited to the pelvic girdle, where males exhibit a more prominent pubic ridge and an ossified symphysis compared to the predominantly cartilaginous structure in females.

The European pond turtle displays distinct anatomical characteristics compared to other turtle species, particularly aquatic ones. Notably, this turtle exhibits nails on all its manus digits, which are elongated and non-fin-like. In conclusion, the use of diagnostic imaging techniques, such as CT scans and micro-CT scans, in the study of turtle skeletons has proven to be highly beneficial. These techniques enable researchers to accurately determine the direction and position of bones, even in species with complex anatomical features like turtles.