« The Seguenziidae are a group of marine snails of worldwide distribution, mostly living in bathyal depths (between 200-1000m) on fine sedimentary substrates. […] They have been considered as either a vetigastropod taxon or an intermediate between Vetigastropoda and Caenogastropoda, showing a perplexing mixture of plesiomorphic and apomorphic characters (Haszprunar 1988; Hickman 1998). Seguenziids are common in collections of deep-water mollusks, but never in large numbers and almost never collected alive; therefore, their classification is almost completely based on shell characters (Quinn 1983b). » – Salvador, Cavallari & Simone: “Seguenziidae (Gastropoda: Vetigastropoda) from SE Brazil collected by the Marion Dufresne (MD55) expedition”, Zootaxa vol.3878(6), p.536.

Shell minute, low spired, with slightly convex to almost flat whorls, a peripheral keel, a weakly convex base bearing a uniform spiral sculpture (the prefix “ancistro” refers to this sculptured basis, furrowed like by an ancistrum, or curved scalpel). Other characteristics are also a thick inner lip and a wide umbilicus.