Tempskya is an extinct genus of tree-shaped ferns, the fossils of which have so far only been found in Cretaceous layers. The Cretaceous is a geologic period and system that spans 79 million years from the end of the Jurassic period 145 million years ago to the beginning of the Paleogene period 66 million years ago.
The stem-shaped structure of Tempskya is called "false stem" because it is formed by an entanglement of large numbers of stems and roots. The upward growing stems, which have a diameter of 2.5-10 mm, gave large numbers of roots (diameter about 1 mm) that grew downwards. They formed a felt-like mass around the stems. Because the stems branched regularly, a very solid whole was created. On a cross section of a trunk (see the images) the relatively large stems and the small roots can be seen.
The trunk was estimated to reach a height of about 6 m and a diameter of 50 cm. A trunk of about 1 meter long has been found. The largest cross section found is about 40 cm. The picture shown here is the reconstruction of the plant by Andrews and Kern (1947).
The pieces of petrified Tempskya, found in Europe, are usually incompletely preserved. In some parts of the United States, such as Idaho and Wyoming, perfect silicified strains have been found. The images shown are taken from slides with very thinly cut petrified Tempskya.
© www.willemsmicroscope.com
With thanks to Hans Steur, Paleobotany
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