Submitted by: Michael Lask
Taxon: Callixylon newberryi
Submit date: 2014-10-04
Location (approximate): Alpena, Alpena, MI
Stratigraphy: Alpena Formation
Age: Erian (Middle Devonian)
Submitter notes: Collected by Patricia Rutkowski from the Antrim Shale of the Paxton Quarry, the specimen is 303 mm long. Callixylon Newberryi is a primitive conifer that dates back to the late Devonian Period, which is considered the time period when trees first evolved. The Callixylon is a member of the extinct order of tree like plants named Archaeopteridales. These plants with fern like leaves are estimated to be 350 to 375 Million years old making them among the worlds oldest trees.
These tree like plants had leaves similar to ferns. For many years scientists classified Archaeopteris as a separate genus than Callixylonin under the order of Archaeopteridales. In the 1960s, paleontologists were able to demonstrate that the fossil wood known as Callixylon and the petrified fern leaf imprints known as Archaeopteris were actually part of the same plant. This plant no matter what it is called has turned out to be the link between trees and ferns.