Lycopodiopsida
Lycopodiella cernua
The Bärlapppflanzen ( Lycopodiopsida ) are a class of vascular plants. It consists of three families with tart herbaceous representatives. In the age of the carbon treelike representatives dominated large areas of the northern hemisphere, they were the basis for today's coal resources in these areas.
- 4.1 Literature
- 4.2 Notes and references
Features
As with the other vascular plants, the sporophyte is the dominant generation here. The sporophyte is branched mostly dichotomously ( dichotomous ). The shoot axes wear simple, not indented leaves that are small and narrow ( Mikrophylle ). From habit, the club mosses similar to mosses, are with these but not closely related than the other vascular plants. The extant representatives are small and herbaceous usually among the fossil representatives were also 40 meter high trees.
The sporangia are individually in the axils or at the base of leaves ( sporophylls ). The sporophylls are usually at the end of shoot sections to Sporophyllständen ( " Blossom" ) combined. There are exceptions for some fossil groups. Most groups are isospor, so they are only equal spores. Some groups moss ferns and Isoetales, are heterosporous, thus form large female and small male spores. The spermatozoids are zweigeißelig usually, a distinguishing feature among the ferns, the other group of vascular cryptogams. Only Isoetes has vielgeißelige spermatozoids.
System
Outer systematics
The Bärlapppflanzen are the sister group to all other vascular plants, the ferns are therefore closer to the seed plants used as the Bärlapppflanzen:
Clubmosses
Isoetales
Selaginellales
Seed plants ( Spermatophyta )
Ferns ( " Monilophyta " )
Inside systematics
The extant members of the class are divided into three orders to the tart, each including only one family:
In addition, there are four orders of extinct Bärlapppflanzen:
- Drepanophycales
- Protolepidodendrales
- Lepidodendrales, such as with the shed trees.
- Pleuromeiales
Paleobotany
The oldest representatives of Bärlapppflanzen have been known since the Silurian, from the Middle Devonian they solved together with the Calamiten the Psilophyten as the dominant group from. In the original representatives of the leaves and sporophylls were dichotomously. Some tree-like agents are among the main representatives of the coal forests of the Carboniferous. In the Carboniferous Bärlapppflanzen had their greatest diversity, especially with the shed trees, which comprise the families Lepidodendraceae and Diaphorodendraceae and Sigillariae. Some tree-like species ranging yet to the Permian, since there is only more herbaceous representatives.