The term
Pteridospermatophyta (or "
seed ferns") refers to several distinct groups of extinct seed-bearing plants (
spermatophytes). The oldest fossil evidence of plants of this type is the genus
Elkinsia of late
Devonian age. They flourished particularly during the
Carboniferous and
Permian periods. Pteridosperms declined during the
Mesozoic Era and had mostly disappeared by the end of the
Cretaceous Period, though some pteridosperm-like plants seem to have survived into
Eocene times,
fossilized in
Tasmania.
