†Onychochilidae is an extinct family of small, fossil, upper Cambrian to lower Devonian molluscs. They have hyperstrophically coiled shells which generally have smooth whorls and elongate apertures. They are commonly considered to be gastropods, i.e. sea snails. Bouchet and Rocroi, 2005 tentatively retained the Onychochilidae in the Gastropoda, including them along with the Clisospiridae in the superfamily Clisospiroidea, and added a third subfamily, the Hyperstropheminae, named for Hyperstrophema Horney, 1964, its sole known genus.