Belongs within: Heterobranchia. The Systellommatophora are a group of slug-like gastropods including the marine Onchidiidae and the terrestrial Veronicelloidea. Members of this group have two pairs of contractile tentacles on the head, with the eyes at the tip of the upper pair, and have the anus and renal opening at the posterior end of the… Continue reading Systellommatophora