Characters such as the long, narrow kidney with reflexed ureter and closed secondary ureter, the penial complex with distinct penis, which is continuous with the epiphallus, epiphallic caecum (a flagellum and an appendix), unbranched gametolytic duct, lack of vaginal accessory organs, and the basic condition of the nervous and retractor muscle systems support the inclusion of "Amphidromus" in the family Camaenidae. This group of snails occur in a wide variety of habitats in the tropics of Eastern Asia and Australasia, and is one of the most diverse families in the clade Stylommatophora. Though Laidlaw & Solem (1961) provided no more additional details on the anatomy of "Amphidromus", subsequent studies by distinct authors, e.g., Bishop (1977) and Solem (1983), have demonstrated that the reproductive system can provide valuable data for species recognition.