The family Pleurodontidae includes some American taxa that used to be included within the Australasian family Camaenidae, a taxon whose monophyly was in doubt. Pleurodontids are defined by a missing diverticulum. However the diverticulum is partially present in the genus Solaropsis. The stimulatory organ is equally missing. However, Solaropsis has in part a penial stimulator and a divided penis retractor muscle.