Crossotheca is an extinct genus of seed ferns widespread in coal measures of Carboniferous, Permian and Triassic age, with possible Devonian remains known from Belgium. The type species is C. crepini,
Sphenopteris is a genus of seed ferns containing the foliage of various extinct plants, ranging from the Devonian to Late Cretaceous. One species, S. höninghausi, was transferred to the genus Crossoth