sentences:  If dissection reveals a two-partite oviduct, one can be sure of "A. distinctus", but in most regions a sizeable proportion of individuals have a three-partite oviduct like that of "A. hortensis".The definitive character, distinguishing "A. distinctus" from all other "Kobeltia" species, is a conical structure inside the atrium that covers the entrance to the epiphallus, but it is not developed in juveniles.The structure is involved in receiving the partner's spermatophore.