Velainellidae is a very small family of gastropods

Gastropoda

The Gastropoda or gastropods, more commonly known as snails and slugs, are a large taxonomic class within the phylum Mollusca. The class Gastropoda includes snails and slugs of all kinds and all sizes from microscopic to quite large...

 containing only the Eocene genus Velainella, named by Vasseur 1880 and found in France. Velainella has a long, narrow, straight twisted shell with a smooth lipped oval aperture. The last whorl is twisted into a slender spiral, simulating a mutlispiral shell but without the spiral septum.

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...

  included the Velainellidae in the vetigastropod superfamily Trochoidea, leaving the rank of the Vetigastropoda undecided. Previously W. F. Ponder and A. Warén 1988 put the Velainellidae in the Loxonematoidea

Loxonematoidea

Loxonematoidea is an extinct taxonomic superfamily of sea snails, marine gastropod molluscs.Families:* † Loxonematidae* † Palaeozygopleuridae...

 (Koken 1889) a superfamily in the Mesogastropoda, Earlier, J. B. Knight, et al, 1960 in the Treatise

Treatise on Invertebrate Paleontology

The Treatise on Invertebrate Paleontology published by the Geological Society of America and the University of Kansas Press, is a definitive multi-authored work of some 50 volumes, written by more than 300 paleontologists, and covering every phylum, class, order, family, and genus of fossil and...

 included the Velainellidae, with Vellainella, in the Trochacea

Trochoidea

Trochoidea may refer to:* Trochoidea , a genus of land snails* Trochoidea , a superfamily of marine snails...

, as does Bouchet & Rocroi, 2005, but in the Archaeogastropoda

Archaeogastropoda

Archaeogastropoda was a taxonomic order of sea snails used in older classifications of gastropods, i.e. snails and slugs. Archeogastropoda are marine prosobranch gastropod mollusks, mainly herbivores, typically having two gills and a double-chambered heart, with the eggs and sperm discharged...

. Trochacea is the original form for what has been changed to Trochoidea.