Lower Heterobranchia
| Lower Heterobranchia | |
|---|---|
| |
| A live animal of Hydatina physis, anterior end towards the top of the image | |
| Scientific classification | |
| Kingdom: | |
| Phylum: | |
| Class: | |
| (unranked): | clade Heterobranchia
informal group Lower Heterobranchia |
| Superfamilies | |
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See text | |
| Synonyms | |
|
Allogastropoda | |
Lower Heterobranchia, also known as the Allogastropoda, is a group of rather specialized, highly-evolved sea slugs and sea snails, (marine gastropod mollusks) within the clade Heterobranchia. Although the great majority of Lower Heterobranchs are indeed marine, a few have succeeded in making the transition to freshwater.
In the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005, the Lower Heterobranchia is an Informal Group.
Description
The shell shapes in this group are typically those that are seen in the sundial, pyramid, rissoella and orbitestellid families of snails.[1]
Taxonomy
Superfamilies within the Lower Heterobranchia include:
- Unassigned to a superfamily (orbitestellid-shells)
- † Family Cimidae
- † Family Dolomitellidae
- † Family Heterosubulitidae
- † Family Kuskokwimiidae
- † Family Misurinellidae
- Family Orbitestellidae
- Family Tjaernoeiidae
- Family Xylodisculidae
- superfamily Acteonoidea
- superfamily Architectonicoidea
- superfamily Glacidorboidea
- † superfamily Nerineoidea
- superfamily Omalogyroidea
- superfamily Pyramidelloidea
- superfamily Ringiculoidea
- superfamily Rissoelloidea
- † superfamily Streptacidoidea
- superfamily Valvatoidea
(Taxa that are exclusively fossil are indicated with a dagger †)
For a more detailed taxonomy see: Taxonomy of the Gastropoda (Bouchet & Rocroi, 2005)#Informal group "Lower Heterobranchia" (= Allogastropoda)