The seed ferns
Callipterids (peltasperms) occur from the upmost Carboniferous. They are seed ferns with characteristic leaves and fructifications. The latter are more or less umbrella-shaped with seeds at the lower side (look at the picture to the right).
The leaves are sized up to one meter, frond-shaped and bearing typical 'intercalary pinnules', leaflets coming directly from the rachis between the partial fronds.
These callipterids are relatively widespread during the Permian. Species
with more or less triangular sporophylls are placed in the genus