Parka (genus)
| Parka Temporal range: Devonian | |
|---|---|
 | |
| Parka decipiens from Devonian of Scotland | |
| Scientific classification | |
| Kingdom: | Plantae |
| Division: | Charophyta |
| Class: | Charophyceae? |
| Order: | Coleochaetales? |
Parka decipiens is a Devonian fossil believed to be an early land plant. It bears at least a passing resemblance to the alga Coleochaete,[1] but the significance of this similarity is yet to be established.[2]
Description
The fossils of Parka decipiens seems small circular, elliptic or irregular patches reaching a diameter of 0.5–7.5 centimetres (0.20–2.95 in), with a reticulate structure showing small coaly discs. These discs contain a mass of what could be spores.[3] Ultrastructural examination of these spores has shown that they lack the y-shaped trilete mark, a Y-like scar, that is characteristic of Silurian and Devonian pteridophytes. [4]
References
- ↑ Delwiche, C.F.; Graham, L.E.; Thomson, N. (1989), "Lignin-Like Compounds and Sporopollenin Coleochaete, an Algal Model for Land Plant Ancestry", Science 245 (4916): 399–401, doi:10.1126/science.245.4916.399, PMID 17744148
- ↑ Kenrick, P.; Crane, P.R. (1997), "The Origin and Early Evolution of Plants on Land", Nature (free full text) 389: 33–39, doi:10.1038/37918
- ↑ The enigmatic plant Parka decipiens
- ↑ Hemsley, A.R. (1989). "The ultrastructure of the spores of the Devonian plant Parka decipiens". Annals of Botany 64 (3): 359–367.
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