Interlabia

(Pleural of Interlabium)Cuticular outgrowths (neoformations)originating at the base of the lips or pseudolabia and extending between them, occurring in some Ascarids and Spirurids(Anderson 1974)

e.g. Exist in Contracaecum spp and absent or have strong reduction in Phocascaris

Their shape is important in Taxonomy

e.g. Contracaecum rudolphii adult stage has  3 Interlabia with characteristic Bifid tip,however L4 larvae of this nematode lacks the interlabia