Lycopsida
Lycopsida (lycopods) Class of the Pterido-phytina, represented today by relatively small plants, the club mosses, although in the Carboniferous they included large trees which dominated the coal-swamp vegetation of the time. The oldest lycopods date from the Devonian and derived from the most primitive of vascular plants, the psilophytes. Lycopods are characterized by dichotomizing branches; spores borne in spore cases (sporangia) on the upper side of the fertile leaves (sporophylls), which are sometimes organized into cones; and ‘microphyllous’ leaves, i.e. with a single strand of vascular tissue proceeding unbrokenly (without a ‘leaf gap’) from the vascular tissue of the stem. The leaves of some lycopods were long and grass like. When they were shed, the leaves left distinctive, spirally arranged leaf scars on the trunk of the lycopod tree. Fragments of the bark are common as fossils in coal balls and the roof shales of Carboniferous coal seams. Prominent genera included Lepidodendron, Lepidophloios, and Sigillaria (in which the spiral leaf-scar pattern fell into discrete vertical rows).
Lycopsida
Lycopsida A subdivision of the Pteridophyta, represented today by the club mosses (families Lycopodiaceae, Selaginellaceae, and Isoetaceae), although in the Carboniferous they included large trees. The oldest lycopods date from the Devonian and derived from the most primitive of vascular plants, the Psilophytopsida.
More From encyclopedia.com
Tracheophyte , tracheophyte Any plant that has elaborate tissues, including vascular tissue; a conspicuous sporophyte generation; and complex leaves with waterproof… Seedless Vascular Plants , The Lycophyta, Equisetophyta, and Psilophyta are collectively referred to as the fern allies because, like the ferns (Pterophyta), they reproduce by… Club Moss , club moss Any of c.200 species of small evergreen spore-bearing plants which, unlike the more primitive true mosses, have specialized tissues for tra… Pinophyta , Pinophyta (pī´nŏf´ətə), division of the plant kingdom consisting of those organisms commonly called gymnosperms. The gymnosperms, a group that includ… Ginkgo , Ginkgo
Ginkgo biloba is a woody tree with a spreading form and a large trunk that reaches a height between fifty to eighty feet. The trees are sexual… Spermatophyte , spermatophyte Seed-bearing plant, including most trees, shrubs, and herbaceous plants. It has a stem, leaves, roots, and a well-developed vascular sy…
About this article
Lycopsida
All Sources -
You Might Also Like
NEARBY TERMS
Lycopsida