Macluritoidea

The Macluritoidea, or Macluritacea as it was originally spelled, is a superfamily of hyperstrophically coiled, Upper Cambrian to Devonian, archaeogastropods,^[1] or paragastropods according to Linsely and Kier (1984).^[2]

Macluritoidea (or Macluritacea) Temporal range: L Cambrian- Devonian
The macluritid Maclurina manitobensis, late Ordovician, Red River Formation, Manitoba (Canada).
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda(?)
Order:	Archaeogastropoda (?)
Superfamily:	Macluridoidea Fisher, 1885

Coiling is dextral, although it appears sinistral,^[1] deduced from the position of the channel (presumed to be exhalent) contained in a ridge or keel (a selenizone on what is assumed to be the upper side. This is supported by the operculum of Maclurites, which corresponds to that of dextral gastropods.

According to the Treatise the Macluritaceae includes two families, the Onychochilidae and Macluritidae. Subsequent placement in the Paragastropoda^[2] is based on the assumption these animals were untorted, that is they lacked the twisted viscera that are present in modern gastropods.