Nematothallus
| Nematothallus | ||||||||||
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| Temporal occurrence | ||||||||||
| Silurian to Lower Devonian | ||||||||||
| Locations | ||||||||||
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Wales u. a. |
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| Systematics | ||||||||||
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| Scientific name | ||||||||||
| Nematothallus | ||||||||||
| WHLang (1937) | ||||||||||
Nematothallus is a group of enigmatic fossils from the Silurian and Devonian that may represent an early form of land plants .
The fossils are flat, thallus - or leaf - like, and a few centimeters in diameter. They consist of a network of tubes, often of two different size classes of tubes. They are covered by a cuticle with a pseudocellular pattern. Such cuticulae are known from the Ordovician to the Lower Devonian . On their inside, the cuticulae have patterns that in vascular plants would be interpreted as the outlines of the epidermal cells. Spores of various sizes are scattered between the tubes and in the cuticle . The association of the tubes, cuticles and spores in the same organism is still not clear. Some of the cuticles have perforations of up to 100 micrometers. The perforations are similar to those of modern liverworts and, like them, could have been used for gas exchange. Other interpretations of the perforations are places of gametes -Freisetzung or wound reactions.
One interpretation of Nematothallus sees them as leaf-like structures of Prototaxites -like axes. But there are no organically connected such finds.
supporting 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.