Known from the Pennsylvanian

• Extinct plants having tall arborescent trunks comparable to or more advanced than cycads
• Probably extinct since the Mesozoic

The Collaborative International Dictionary Word definitions in The Collaborative International Dictionary
Cordaitales \Cordaitales\ n. an order of extinct plants having tall arborescent trunks comparable to or more advanced than cycads; known from the Pennsylvanian; probably extinct since the Mesozoic. Syn: order Cordaitales .

Wikipedia Word definitions in Wikipedia
Cordaitales are an extinct order of woody plants that may have been early conifers , or which may have given rise to the conifers ( Pinophyta ), ginkgos ( Ginkgophyta ) and cycads ( Cycadophyta ). They had cone-like reproductive structures reminiscent of ...