Cycloneritida | |
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Family Neritidae: Nerita plicata on intertidal rock surfaces at Turtle Island, Fiji | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Mollusca |
Class: | Gastropoda |
Subclass: | Neritimorpha |
Order: | Cycloneritida |
Superfamilies | |
See text | |
Synonyms | |
Cycloneritimorpha |
Cycloneritida (nerites and false-limpets) is an order of land snails, freshwater snails, and sea snails.[1]
These are gastropod molluscs within the subclass Neritimorpha. 14 of the families in the order are extant, and eight of the families are extinct.
It was previously categorized as the clade Cycloneritimorpha.[2]
According to the Taxonomy of the Gastropoda (Bouchet & Rocroi, 2005), as well as the Cycloneritida, the subclass 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]