Cycloneritimorpha

Cycloneritimorpha
Family Neritidae: Nerita plicata on intertidal rock surfaces at Turtle Island, Fiji
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda
(unranked):	clade Neritimorpha
(unranked):	clade Cycloneritimorpha Frýda, 1998[1]
Families
See text

Cycloneritimorpha (nerites and false-limpets^[2]) is a clade of land snails, freshwater snails, and sea snails. These are gastropod molluscs within the larger clade Neritimorpha. 14 of the families in the clade are extant, and eight of the families are extinct.

According to the Taxonomy of the Gastropoda (Bouchet & Rocroi, 2005), as well as the Cycloneritimorpha, the clade Neritimorpha also contains the (entirely fossil) clade Cyrtoneritimorpha, plus a number of other fossil families that are currently unassigned.

The earliest evolutionary forms of Cycloneritimorpha show double visceral organs, double gills, and normally a double-chambered heart.^[3]

Taxonomy

The taxonomy of Cycloneritimorpha is based on work by Kano et al. (2002),^[4] that recognizes 4 clades. These clades are established on genetic analysis (28S rRNA) of recent species only. These clades proposed by Kano are ranked as superfamilies in taxonomy of the Gastropoda (Bouchet & Rocroi, 2005).

Clade Cycloneritimorpha contains:

• Superfamily Helicinoidea
  • Family Helicinidae
  • † Family Dawsonellidae
  • † Family Deaniridae
  • Family Neritiliidae
  • Family Proserpinellidae
  • Family Proserpinidae
• Superfamily Hydrocenoidea
  • Family Hydrocenidae
• Superfamily Neritoidea
  • Family Neritidae
  • Family Phenacolepadidae
  • † Family Pileolidae
• Superfamily Neritopsoidea
  • Family Neritopsidae
  • † Family Cortinellidae
  • † Family Delphinulopsidae
  • † Family Plagiothyridae
  • † Family Pseudorthonychiidae
  • Family Titiscaniidae
• Superfamily Symmetrocapuloidea
  • † Family Symmetrocapulidae

References

2. "Neritimorpha - Cycloneritimorpha". Molluscsoftasmania.net. Retrieved 2015-08-25.
3. "Gastropoda - Snails, Slugs, Limpets, Nudibranchs". Discover Life. Retrieved 2015-08-25.
4. Kano Y., Chiba S. & Kase T. 2002. Major adaptive radiation in neritopsine gastropods estimated from 28S rRNA sequences and fossil records. Proceedings of the Royal Society of London, B, 269: 2457-2465.