Tempskya is an extinct genus of tree fern that lived during the Cretaceous period. Fossils have been found across both the Northern and Southern hemispheres. The growth habit of Tempskya was unlike that of any living fern or any other living plant, consisting of multiple conjoined dichotomous branching stems enmeshed within roots that formed a "false trunk"

The trunk of Tempskya was actually a large collection of stems surrounded by adventitious roots. The false trunks can reach up to 6 meters (20 ft) in height and up to 50 centimeters (20 in) in diameter. Small leaves grew from various points across the height of the trunk. This contrasts with most tree ferns, where typically large leaves grow from the top of the trunk. Thin leaves have been discovered for the first time on Tempskya wyomingense specimens; the more commonly seen fossilized leaf bases show that they cover the upper part of the trunk.