– An online study & reference for reserchers, students in botany with full reference on research institutes and scientific. Division Equisetophyta. Stanley L. Welsh. Monte L. Bean Life Science Museum and Department of Botany and Range Science, Brigham Young. Welsh, Stanley L.; Atwood, N. Duane; Goodrich, Sherel; and Higgins, Larry C. ( ) “Division Equisetophyta,” Great Basin Naturalist Memoirs: Vol. 9, Article 7.

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“Division Equisetophyta” by Stanley L. Welsh, N. Duane Atwood et al.

This contrasts with the seed plants, which grow from an apical meristem – i. From Wikipedia, the free encyclopedia.

Equisetopsidaor Sphenopsidais a class of vascular plants with a fossil record going back to the Devonian. The extant horsetails are homosporousbut extinct heterosporous species such as Calamostachys casheana appear in the fossil record. New York and London: By using this site, you agree to the Terms of Use and Privacy Policy.

The horsetails and their fossil relatives have long been recognized as distinct from other seedless vascular plants. Sphenophyllales Archaeocalamitaceae Calamitaceae, A.

Division: Equisetophyta

The Sphenophytes comprise photosynthesising, “segmented”, hollow stems, sometimes filled with pith. Charophytes basal Streptofilum Klebsormidiophyceae. The Origin and early diversification of land plants: Similar spaces, the vallecular canals equisetopyhta formed in the cortex.

The spores bear characteristic elatersdistinctive spring-like attachments which are hygroscopic: American Journal of Botany.

Archived from the original PDF on See also the list of plant orders.

The underground parts of the plants consist of jointed rhizomesfrom which roots and aerial axes emerge. In other projects Wikimedia Commons Wikispecies. These cones comprise spirally arranged sporangiophoreswhich bear sporangia at their edges, and in extant sphenophytes cover the spores externally – like sacs hanging from an umbrella, with its handle embedded in the axis of the cone. The Equisetales existed alongside the Sphenophyllalesbut diversified as that group disappeared into extinction, gradually dwindling in diversity to today’s single genus Equisetum.


Other authors have regarded the same group as a class, either within a division consisting of the vascular plants or, more recently, within an expanded fern group. Recent phylogenetic analysis has produced evidence that this group of plants belongs firmly within the fern clade of vascular plants.

Articles with ‘species’ microformats All articles with unsourced statements Articles with unsourced statements from July Commons category link is on Wikidata. They are commonly known as horsetails. Glaucocystophyceae Glaucocystis Cyanophora Gloeochaete. The Equisetopsida were formerly regarded as a separate division of spore plants and also called EquisetophytaArthrophytaCalamophyta or Sphenophyta ; today they have been recognized as rather close relatives of the typical ferns Pteridopsida and form a specialized lineage of the Pteridophyta.

Charophyceae Coleochaetophyceae Zygnematophyceae Mesotaeniaceae.

Equisetopsida – Wikipedia

Morphology of vascular plants Lower Groups. The origin of the land flora, a theory based upon the facts of alternation. Paleobotany and the evolution of plants 2nd ed. International Journal of Plant Sciences.

At the junction “node”, see equksetophyta between each segment is a whorl of leaves. In the only extant genus Equisetumthese are small leaves microphylls with a singular vascular trace, fused equistophyta a sheath at each stem node. Cyanidiophyceae Porphyridiophyceae Compsopogonophyceae Stylonematophyceae Rhodellophyceae Bangiophyceae Florideophyceae.

Wikimedia Commons has media related divison Equisetopsida. When ranked as a class, the group has been termed the Equisetopsida [14] or Sphenopsida. The plants have intercalary meristems in each segment of the stem and rhizome that grow as the plant gets taller. A recent study by Elgorriaga et al. Plant systematics, a phylogenetic approach.


The organisms first appear in the fossil record during the late Devonian, [9] a time when land plants were undergoing a rapid diversification, with roots, seeds and leaves having only just evolved.

Data related to Equisetopsida at Wikispecies. In extinct groups, further protection was afforded to the spores by the presence of whorls of bracts – big pointed microphylls protruding from the cone.


However, the leaves of Equisetum probably arose by the reduction of megaphyllsdiviaion evidenced by early fossil forms such as Sphenophyllumin which the leaves are broad with branching veins.

This page was last edited on 28 Novemberat The biology and evolution of fossil plants. Sphenophytes bear cones technically strobilising. The vascular bundles trifurcate at the nodes, with the central branch becoming the vein of a microphyll, and the other two moving left and right to merge with the new branches of their neighbours.

All extant species of Equisetum are herbaceous, and divieion lost the ability to produce secondary growth. Retrieved from ” https: Views Read Edit View history.