query: parent_taxon xanthonychidae
supports: Xanthonychidae is a family of air - breathing land snails , terrestrial pulmonate gastropod mollusks in the superfamily Helicoidea . This family is within the clade Eupulmonata ( according to the taxonomy of the Gastropoda by Bouchet & Rocroi , 2005 ) . Snail is a common name that is applied most often to land snails, terrestrial pulmonate gastropod molluscs. However, the common name "snail" is also applied to most of the members of the molluscan class Gastropoda that have a coiled shell that is large enough for the animal to retract completely into. When the word "snail" is used in this most general sense, it includes not just land snails but also thousands of species of sea snails and freshwater snails. Occasionally a few other molluscs that are not actually gastropods, such as the Monoplacophora, which superficially resemble small limpets, may also informally be referred to as "snails". Stylommatophora is a taxon of air-breathing land snails and slugs, terrestrial pulmonate gastropod molluscs. This taxon is considered to be a clade. It used to be regarded as an infraorder (also sometimes was considered to be an order). This taxon includes the majority of land snails and slugs. Helicoidea is a taxonomic superfamily of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the clade Stylommatophora.
candidates: gastropoda helicoidea stylommatophora
answer: stylommatophora