Pachytheca

Pachytheca is a fossil genus, which is often discussed as a possible early land plant. It dates from the upper Silurian to Middle Devonian.

The specimens are rather small with 0.1 to 0.6 centimeters in diameter. They are spherical and consist of two different zones. The inner zone, called the medulla, consists of densely packed, intertwined tubes. The outer zone, called bark consists of radially disposed tubes. Between cortex and medulla is a narrow zone in which replace the tubes between random and orderly arrangement. In some instances there is a channel that connects with the exterior of the medulla.

An interpretation of Pachytheca than spreading unit ( Cystokarp ) of Prototaxites. However, there are no known organic associated finds. Another interpretation sees Pachytheca as a juvenile form of Parka decipiens.

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. Pp. 183f.

• Extinct plant
• Eukaryotes
• Eukaryota