Standard karyotypes of carettochelyid and trionychid turtles are similar. The pitted-shelled turtle, Carettochelys insculpta (2n=68), and three species of softshelled turtles, Trionyx spiniferus, T. ferox and T. sinensis (2n=66) were examined. Chromosomal banding patterns are the same among the species of Trionyx studied, but substantially different from non-trionychoid turtles. Karyotypic similarity supports previous morphological studies that indicate the families Carettochelyidae and Trionychidae are closely related or that both families are distantly related to other turtles.
The Japan Mendel Society