Kittlidiscidae is an extinct family of Middle Triassic

Triassic

The Triassic is a geologic period and system that extends from about 250 to 200 Mya . As the first period of the Mesozoic Era, the Triassic follows the Permian and is followed by the Jurassic. Both the start and end of the Triassic are marked by major extinction events...

 gastropods in the superfamily Pleurotomarioidea

Pleurotomarioidea

Pleurotomarioidea is a superfamily of small to large marine gastropods included in the Vetigastropoda.These are the slit shells, originally named Pleurotomariacea, in keeping with the convention for naming superfamilies at the time....

, named to contain the genus Kittlidiscus and included in the Vetigastropoda

Vetigastropoda

Vetigastropoda is a major taxonomic group of sea snails, marine gastropod mollusks that form a very ancient lineage. Taxonomically Vetigastropoda are sometimes treated as an order although they are a clade in Bouchet and Rocroi, 2005....

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Note that Bouchet & Rocroi, 2005

Taxonomy of the Gastropoda (Bouchet & Rocroi, 2005)

The taxonomy of the Gastropoda as it was revised by Philippe Bouchet and Jean-Pierre Rocroi is currently the most up-to-date overall system for classifying gastropod mollusks...

gives Vetigastropoda simply as a clade, which not being paraphyletic, it also is, leaving taxonomic ranking to a future date. Other gastropod classifications, including those subsequent, have determined that the Vetigastropoda is a superorder.