Lower Heterobranchia

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 subclass Heterobranchia. [1]

Lower Heterobranchia
A live individual of Architectonica perspectiva
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda
Subclass:	Heterobranchia
Infraclass:	Lower Heterobranchia
Superfamilies
See text

Although the great majority of Lower Heterobranchs are indeed marine, a few have succeeded in making the transition to freshwater.

Description

The shell shapes in this group are typically those that are seen in the sundial, pyramid, rissoella and orbitestellid families of snails.[2]

Bactroptyxis trachaea, family Nerineidae, superfamily Nerineoidea.

Valvata piscinalis, family Valvatidae, superfamily Valvatoidea.

Taxonomy

2005 taxonomy

In the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005,[3] the Lower Heterobranchia is an Informal Group. 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 Mathildoidea
• † 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)

2010 taxonomy

Jörger et al. (2010)[4] have redefined major groups within the Heterobranchia: they moved Glacidorboidea and Pyramidelloidea to Panpulmonata.[4]

2014 taxonomy

Wägele et al. (2014):[5] moved Rissoelloidea and Acteonoidea from Lower Heterobranchia to Euthyneura.

2016 taxonomy

Kano et al. (2016):[6] moved Ringiculoidea from Lower Heterobranchia to Euthyneura.

So the following taxa remain within the Lower Heterobranchia:

• Unassigned to a superfamily (orbitestellid-shells)
  • Family Cimidae
  • † Family Dolomitellidae
  • † Family Heterosubulitidae
  • † Family Kuskokwimiidae
  • † Family Misurinellidae
  • Family Orbitestellidae
  • Family Tjaernoeiidae
  • Family Xylodisculidae
• superfamily Architectonicoidea
• superfamily Mathildoidea
• † superfamily Nerineoidea
• superfamily Omalogyroidea
• † superfamily Streptacidoidea
• superfamily Valvatoidea

References

1. WoRMS (2020). "Lower Heterobranchia". Accessed at: https://www.marinespecies.org/aphia.php?p=taxdetails&id=1054700 on 2020-05-16
2. http://www.molluscsoftasmania.net/Subclass%20pages/Heterobranchia.html
3. Bouchet, Philippe; Rocroi, Jean-Pierre; Frýda, Jiri; Hausdorf, Bernard; Ponder, Winston; Valdés, Ángel & Warén, Anders (2005). "Classification and nomenclator of gastropod families". Malacologia. Hackenheim, Germany: ConchBooks. 47 (1–2): 1–397. ISBN 3-925919-72-4. ISSN 0076-2997.
4. Jörger K. M., Stöger I., Kano Y., Fukuda H., Knebelsberger T. & Schrödl M. (2010). "On the origin of Acochlidia and other enigmatic euthyneuran gastropods, with implications for the systematics of Heterobranchia". BMC Evolutionary Biology 10: 323. doi:10.1186/1471-2148-10-323.
5. Wägele H., Klussmann-Kolb A., Verbeek E. & Schrödl M. (2014). "Flashback and foreshadowing—a review of the taxon Opisthobranchia". Organisms Diversity & Evolution 14(1): 133–149. doi:10.1007/s13127-013-0151-5
6. Kano, Yasunori; Brenzinger, Bastian; Nützel, Alexander; Wilson, Nerida G.; Schrödl, Michael (2016-08-08). "Ringiculid bubble snails recovered as the sister group to sea slugs (Nudipleura)". Scientific Reports. 6: 30908. doi:10.1038/srep30908. ISSN 2045-2322. PMC 4976385. PMID 27498754.