Coleochaetales: Fossil Record


The Coleochaetales are known in the fossil record only as Parka decipiens, shown below, which morphologically resembles some members of the living genus Coleochaete. Fossils of Parka have been found from the Upper Silurian to Lower Devonian, strata about 400 million years old. This means that they were present at about same time as the appearance of the first land plants.

Fossil specimens range from 0.5 to 7.0 centimeters in diameter. They are discoid, and apparently had a pseudoparenchymatous organization. On the surface of the disc are oval structures which may be zygotes or sporangia. They contain what have been interpreted as spores, though no trilete mark has been found on them.

You may click on the above image for another image which shows the size and scale of the fossil, or click here for a larger version of the same image (200K).



Source: The Biology and Evolution of Fossil Plants by Thomas N. and Edith L. Taylor, 1993 Prentice Hall, NJ.