'', a
pleurobranch.
Current taxonomy Source:
Heterobranchia •
Lower Heterobranchia •
Valvatoidea Gray, 1840 •
Architectonicoidea Gray, 1850 •
Mathildoidea Dall, 1889 •
Omalogyroidea G. O. Sars, 1878 • Allomorpha •
Murchisonelloidea Casey, 1904 •
Rhodopoidea Ihering, 1876 •
Orbitestelloidea Iredale, 1917 •
Cimoidea Warén, 1993 •
Euthyneura •
Actenonacea •
Acteonoidea d'Orbigny, 1843 •
Rissoelloidea Gray, 1850 •
Tjaernoeiidae Warén, 1991 •
Ringipleura •
Ringiculoidea Philippi, 1853 •
Nudipleura •
Tectipleura •
Euopistobranchia •
Panpulmonata Older taxonomy The families currently included in Heterobranchia have historically been placed in many different parts of the taxonomic class of gastropods. Earlier authors (such as
J.E. Gray, 1840) considered Heterobranchia to consist of only marine gastropods, and conceptualized it as a borderline category, intermediate between the
Opisthobranchia &
Pulmonata, and all the other gastropods. The (sometimes recognized) category
Heterostropha within the Heterobranchia, which includes such families as
Architectonicidae, the sundial or staircase snails, is primarily characterized by a shell which has a heterostrophic
protoconch, in other words the apical whorls are coiled in the opposite plane to the adult whorls. The classification of this group was revised by
Ponder & Warén in 1988. According to the older
taxonomy of the Gastropoda (Ponder & Lindberg, 1997) the Heterobranchia were ranked as a superorder.
2005 taxonomy phylogenetic tree shows that there is no clade-supporting pattern for the monophyly of Opisthobranchia (green) or of Pulmonata (yellow) based on datasets by Jörger et al. (2010). A
cladogram showing phylogenic relations of Heterobranchia as proposed by Jörger et al. (2010): |1=
Valvatoidea |barbegin1=blue |2=}}}} ==References==