Ullmannia
| Ullmannia | ||||||||||||
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Fossil of Ullmannia bronni |
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| Temporal occurrence | ||||||||||||
| Upper Permian | ||||||||||||
| 270 to 251 million years | ||||||||||||
| Locations | ||||||||||||
| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Ullmannia | ||||||||||||
| Goepp. |
The Ullmanniaceae with the only genus Ullmannia are an extinct family from the order of the Voltziales . The Ullmanniaceae were common in the Permian North America and Europe.
features
The vegetative branches of the Ullmanniaceae have lanceolate to oval leaves that are up to eight centimeters long. The construction is extremely xeromorphic . The stomata are partly deeply sunk, monocyclic and are located on both sides of the leaf (amphistomatic). They are arranged in interrupted rows. There are papillae on some epidermal cells .
In Ullmannia , the female cones are up to six centimeters long, their bracts have a pointed apex. The short shoots are strongly flattened, the individual scales are fused together, similar to the seed scales of recent pine trees. In the Ullmanniaceae, however, the flattened short shoot is still free of its bract. A single ovule sits on the adaxial surface of the fertile scale of Ullmannia frumentaria (pointing to the axis) .
The male cones are simple, the elongated pollen sacs are abaxial (at the bottom).
supporting documents
- Thomas N. Taylor, Edith L. Taylor: The Biology and Evolution of Fossil Plants . Prentice Hall, Englewood Cliffs 1993, pp. 681f. ISBN 0-13-651589-4