†family Cremnorthidae Williams 1963 (lamp shell)
Rhynchonellata - Orthida - Cremnorthidae
Parent taxon: Plectorthoidea according to A. Williams et al. 2000
See also Mitchell 1977 and Potter 1990
Sister taxa: Apatoskenidioides, Chilcorthidae, Cyclocoeliidae, Eoorthidae, Euorthisinidae, Finkelnburgiidae, Giraldiellidae, Lebediorthis, Nanorthidae, Phragmorthidae, Platystrophiidae, Plectorthidae, Ranorthidae, Rhactorthidae, Tasmanorthidae, Wangyuiidae
Subtaxa: Brandysia Cremnorthinae Cremnorthis Septorthis
Ecology: stationary epifaunal suspension feeder
Distribution: