Eusphenopteris Seed Fern Fossil

Pteridosperms or seed ferns are a group of extinct plants with mostly fern-like foliage but having real seeds. They were mostly small trees but other forms that exhibited climbing growth have been found. Some forms, notably those called the Medullosales as seen here had large fronds which could be up several meters long. Several groups can be distinguished within the Pteridosperms. The Pteridosperms evolved in the latest Devonian, and became common in the Carboniferous. The Medullosales took over the leading role during the Westphalian and persisted into the Permian. This fossil contains frond segments with numerous pinnules of Neuropteris, a seed fern genus charactrerized by rounded leaflets that are nomally blunt at the tips. The specimen comes from the Fire Creek Formation (coal country), West Viginia, and dates to the Lower Pennsylvanian.