Sphenopteris sp. is the name given to the foliage of several different types of plants. Some of these plants are ferns; others are seed ferns.
Seed ferns (Pteridospermales) are an extinct group of gymnosperms. Although their foliage resembled that of modern ferns, they reproduced by means of seeds. Modern ferns reproduce by means of spores.
Some seed ferns were small trees; others are reconstructed as lianas or vines.