Pteridosperms, also known as seed ferns, are a polyphyletic grouping of extinct seed-producing plants. The earliest fossil evidence for plants of this type are the lyginopterids of late Devonian age.

The Callistophytaceae was a family of seed ferns from the Carboniferous and Permian periods. They first appeared in late Middle Pennsylvanian times, 306.5–311.7 million years ago in the tropical coal