Nematothallus

Wales, inter alia,

Nematothallus is a group of enigmatic fossils from the Silurian and Devonian, which might represent an early form of land plants.

The fossils are flat, thallus or leaf -like, and have a diameter of a few centimeters. They consist of a network of tubes, often from two different size classes of tubes. They are covered by a cuticle with a pseudo- cellular pattern. Such cuticles are known from the Ordovician to the Lower Devonian. On its inside the cuticles have patterns that would be interpreted in vascular plants as the contours of the epidermal cells. Between the tubes and in the cuticle spores of various size are scattered. The togetherness of the tubes, cuticles and spores of the same organism is still not clear. Some of the cuticles have perforations of up to 100 microns. The perforations are similar to those of modern liverworts and how these might have served the gas exchange. Other interpretations for the perforations are places of gamete release or wound reactions.

An interpretation of Nematothallus she sees as a leaf -like structures of Prototaxites -like axes. But there is no such organically related finds.

Documents

• Thomas N. Taylor, Edith L. Taylor, Michael Krings: Paleobotany. The Biology and Evolution of Fossil Plants. Second Edition, Academic Press 2009, ISBN 978-0-12-373972-8, p 183

• Extinct plant
• Eukaryotes
• Eukaryota