Seguenzioidea is a superfamily of minute to medium-sized sea snails, marine gastropod mollusks in the clade Vetigastropoda.
The distinctive characteristics of the shells of the Seguenzioidea are:
the nacreous layer (a plesiomorphic character, i.e. a character state that a taxon is inferred to have been retained from its ancestors) This occurs also in the following families: Pleurotomariidae, Haliotidae, Turbinidae, Trochidae, and possibly in the Skeneidae.the protoconch has a trochoid shape.usually with one or more labral sinuses. This character is also found is several other superfamilies such as Neomphaloidea, Pleurotomarioidea, Fissurelloidea, and Scissurellidea and in the families Siliquariidae and Turridae. Therefore, this characteristic is to be considered autapomorphic.a unique radular formula with an underlying rhipidoglossate ground plan.This superfamily was placed in part or in whole previously to 1979 either in the Archaeogastropoda near the superfamily Trochoidea or in the Caenogastropoda near the superfamily Stromboidea. In 1987 Salvini-Plawén and Haszprunar changed its status to the suborder Seguenziina, based on the radular formula that they considered to be intermediate between "rhipidoglossate" and "taenioglossate". At about the same time in 1987 Goryachev elevated the superfamily to ordinal status Seguenziiformes in the superorder Littorinimorpha, based on the taenioglossal radula.
2005 taxonomy according to Bouchet & Rocroi, 2005. (Families that are exclusively fossil are indicated with a dagger †.)
Superfamily Seguenzioidea
Kano et al. (2009) elevated the subfamily Calliotropinae to the family level as the Calliotropidae, and the subfamily Cataeginae to family level as the Cataegidae.
The superfamily Seguenzioidea consists of six families:
Family CalliotropidaeFamily CataegidaeFamily ChilodontidaeFamily EucyclidaeFamily LaubellidaeFamily SeguenziidaeUnassigned to a family:Adeuomphalus Seguenza, 1876 Aequispirella Finlay, 1924Akritogyra Warén, 1992Anekes Bouchet & Warén, 1979Benthobrookula A. H. Clarke, 1961Brookula Iredale, 1912Eudaronia Cotton, 1945Granigyra Dall, 1889Lissotesta Iredale, 1915Lissotestella Powell, 1946Microcarina Laseron, 1954Moelleriopsis Bush, 1897Notosetia Iredale, 1915Palazzia Warén, 1991Putilla A. Adams, 1867Retigyra Warén, 1989Trenchia Knudsen, 1964Ventsia Warén & Bouchet, 1993Vetulonia Dall, 1913Wanganella Laseron, 1954Xyloskenea B. A. Marshall, 1988Unassigned genera brought into synonymyAbyssogyra A.H. Clarke, 1961: synonym of Moelleriopsis Bush, 1897Intortia Egorova, 1972: synonym of Lissotesta Iredale, 1915Molleriopsis : synonym of Moelleriopsis Bush, 1897
