Architectonicoidea is a

superfamily SUPERFAMILY is a database and search platform of structural and functional annotation for all proteins and genomes. It classifies amino acid sequences into known structural domains, especially into SCOP superfamilies. Domains are functional, str ...

of sea snails, marine gastropod

mollusk Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is es ...

s in the informal group Lower Heterobranchia.Bouchet P. & Rocroi J.-P. (Ed.); Frýda J., Hausdorf B., Ponder W., Valdes A. & Warén A. 2005. ''Classification and nomenclator of gastropod families''. Malacologia: International Journal of Malacology, 47(1–2). ConchBooks: Hackenheim, Germany. . . 397 pp. http://www.vliz.be/Vmdcdata/imis2/ref.php?refid=78278 This superfamily contains the

extant Extant is the opposite of the word extinct. It may refer to: * Extant hereditary titles * Extant literature, surviving literature, such as ''Beowulf'', the oldest extant manuscript written in English * Extant taxon, a taxon which is not extinct, ...

family

Architectonicidae Architectonicidae, common name the staircase shells or sundials, are a family of sea snails, marine gastropod mollusks in the informal group "Lower Heterobranchia" (= Allogastropoda) of the clade Heterobranchia. The extinct families † Amph ...

and also contains the extinct families Amphitomariidae and Cassianaxidae.

References

Lower Heterobranchia Taxa named by John Edward Gray {{Heterobranchia-stub