It includes at least one valid family, Peltaspermaceae, which spans from the Permian to Early Jurassic, which is typified by a group of plants with Lepidopteris leaves, Antevsia pollen-organs, and Peltaspermum ovulate organs, though the family now also includes other genera like Peltaspermopsis, Meyenopteris and Scytophyllum.

[3] Along with these, two informal groups (the "Supaioids"[4][5] and the "Comioids"[6]) of uncertain taxonomic affinities exist, each centered around a specific genus; Supaia and Comia, known from the Early Permian of the Northern Hemisphere, especially of North America.

The leaves of many peltasperms have "monocyclic stomata with wedge-shaped subsidiaries ending in a beak-like papilla overarching the guard cells", something which is found among other seed plant groups.

[2] Some authors have suggested that some peltasperms may have close affinities to corystosperms, another group of extinct "seed ferns".

from the Battle Camp Formation of Clack Island, of latest Jurassic or earliest Cretaceous age may indicate an even longer survival in Gondwana.