An incidental observation in a control male was calculi in the caudal sperm duct. These circular bodies had a diameter of approx. 100 µm, and showed a concentric layer structure. At low magnification, these calculi had an oocyte-like appearance (upper image), and the animal could easily be diagnosed as an intersex (see ovo-testis). However, at high magnification (lower image), it was evident that these bodies consisted of calcium deposits, encapsulated with a sheath of reactive cells.

These intratesticular calculi are of unknown cause, and have also been described in mammals.