Lycopod
| Lycopod Temporal range: Silurian to Recent
| |
|---|---|
| |
| Lycopodiella inundata | |
| Scientific classification | |
| Kingdom: | |
| Division: | Lycopodiophyta |
The Lycopods (Lycopodiophyta or Lycophyta) are the oldest surviving vascular plant division. This is a subdivision of the plant kingdom. Its earliest fossils are from 428–410 million years ago.[3][4]p99
The Lycopods include some of the most primitive (basal) living species. They reproduce by shedding spores and have macroscopic alternation of generations.[5] Members of Lycopodiophyta have a protostele,[6] and the sporophyte generation is dominant.[7][8]
Lycopods differ from all other vascular plants in having microphylls, leaves that have only a single vein rather than the much more complex megaphylls found in ferns and seed plants.
The first coalfields
[change | change source]The lycopods, or club mosses, are the main plants in the Carboniferous rain forests. They were only partly eaten by insects and other life-forms. Mostly they formed swamplands which in the course of time became coal measures. In fact most of the coal from the Carboniferous period comes from these swamplands.[9]
Classification
[change | change source]There are around 1,200 living species of Lycopodiophyta; they are generally divided into three orders.[10] There are also some extinct groups. There are different opinions as to how the whole group should be classified.[11][12]p8 Living groups are:
References
[change | change source]- ↑ Cronquist, A; Takhtajan, A.; Zimmermann, W. (1966). "On the higher taxa of Embryobionta". Taxon. 15 (15): 129–134. doi:10.2307/1217531. JSTOR 1217531.
- ↑ Cantino, Philip D.; et al. (2007). "Towards a phylogenetic nomenclature of Tracheophyta". Taxon. 56 (3): E1–E44. doi:10.1002/tax.563001.
- ↑ Kenrick, Paul; Crane, Peter R. (1997). The origin and early diversification of land plants: a cladistic study. Washington D.C.: Smithsonian Institution Press. pp. 339–340. ISBN 1-56098-730-8.
- ↑ McElwain, Jenny C; et al. (2002). The evolution of plants. Oxford: Oxford University Press. ISBN 0-19-850065-3.
- ↑ 'macroscopic' = can be seen with the naked eye, e.g. instead of requiring a microscope
- ↑ A central core of vascular tissue which conducts water and nutrients up, and manufactured substances down. The stele also supports the plant above the ground.
- ↑ The sporophyte generation is diploid, and produces the spores. The spores produce the haploid gametophyte generation.
- ↑ Eichhorn, Evert, and Raven 2005. Biology of plants, 7th ed. 381-388.
- ↑ Gensel P.G. & Edwards D. (eds). Plants invade the land : evolutionary & environmental perspectives. New York: Columbia University Press. ISBN 978-0-231-11161-4
- ↑ Callow, R.S.; Cook, Laurence Martin (1999). Genetic and evolutionary diversity: the sport of nature. Cheltenham: S. Thornes. p. 8. ISBN 0-7487-4336-7.
- ↑ Yatsentyuk, S.P.; et al. (2001). "Evolution of Lycopodiaceae inferred from spacer sequencing of chloroplast rRNA genes". Russian Journal of Genetics. 37 (9): 1068–73. doi:10.1023/A:1011969716528. S2CID 22187626.
- ↑ Schoch CL; et al. (2020). "NCBI Taxonomy: a comprehensive update on curation, resources and tools". Database : The Journal of Biological Databases and Curation. 2020. doi:10.1093/database/baaa062. PMC 7408187. PMID 32761142. Retrieved 2009-03-19.