†suborder Diffingiina Fedorowski 1985 (horn coral)
Full reference: J. Fedorowski. 1985. Diffingiina, a new suborder of the rugose corals from SW Texas. Acta Palaeontologica Polonica 30:209-240
Parent taxon: Stauriida according to J. Fedorowski 1985
Sister taxa: Arachnophyllina, Aulophyllina, Calostylina, Caniniina, Columnariina, Cyathophyllina, Hillia, Ketophyllina, Kleopatrinidae, Lithostrotionina, Lomaphyllum, Lonsdaleiina, Lophophyllidiidae, Lophotichiidae, Lycophyllina, Metriophyllina, Mictocystoides, Petalaxidae, Petraphyllidae, Plerophyllina, Ptenophyllina, Stauriina, Stereolasmatina, Streptelasmatina, Yatsengiidae
Subtaxa: Diffingiidae, Plerodiffiidae
Ecology: stationary epifaunal suspension feeder