Trochonanininae

Hyman, Isabel T. & Ponder, Winston F., 2010, A morphological phylogenetic analysis and generic revision of Australian Helicarionidae (Gastropoda: Pulmonata: Stylommatophora), and an assessment of the relationships of the family 2462, Zootaxa 2462 (1), pp. 1-148 : 92

Subfamily Trochonanininae

Remarks. Since Baker’s (1941a) revision of the relationships of the Limacoidea s. l., Trochonanininae has been recognised as a subfamily of Urocyclidae and usually synonymised with Trochozonitinae ( Baker 1941a; Hausdorf 1998; Solem 1966). In contrast, Schileyko (2002b) separated Trochozonitinae and Trochonanininae , citing differences in the flagellum, caecum, penial complex and stimulator. Both groups were treated as subfamilies of Ariophantidae ; however, as discussed earlier ( Helicarionidae : Remarks), the characters Schileyko (2002b, 2003a) used to separate Ariophantidae and Helicarionidae are shown in the current study to be flawed. This makes it difficult to evaluate Schileyko’s changes so we follow the traditional classification, with key characters defined as follows:

Shell complete or somewhat reduced. Penis retractor muscle attached to epiphallus instead of epiphallic caecum (except Trochozonites Pfeffer, 1883 ); flagellum absent or present, lime-sac absent; stimulator absent or present.