– 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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This page was last edited on 28 Novemberat All extant species of Equisetum are herbaceous, and have lost the ability to produce secondary growth. They are commonly known as horsetails. According to that study, the age of the crown group of Equisetum dates at least to the Early Cretaceous, and most probably up to the Jurassic.

Charophytes basal Streptofilum Klebsormidiophyceae. The Sphenophytes comprise photosynthesising, “segmented”, hollow stems, sometimes filled with pith. The origin of the land flora, a theory based upon the facts of alternation. When recognized as a separate division, the literature uses many possible names, including Arthrophyta, [12] Calamophyta, Sphenophyta, [1] [13] or Equisetophyta. 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.

Cyanidiophyceae Porphyridiophyceae Compsopogonophyceae Stylonematophyceae Rhodellophyceae Bangiophyceae Florideophyceae. In other projects Wikimedia Commons Wikispecies. In the only extant genus Equisetumthese are small leaves microphylls with a singular vascular trace, fused into a sheath at each stem node. However, the leaves of Equisetum probably arose by the reduction of megaphyllsas evidenced by early fossil forms such as Sphenophyllumin which the leaves are broad with branching veins.


When ranked as a class, the group has been termed the Equisetopsida [14] or Sphenopsida. A recent study by Elgorriaga et al. See also the list of plant orders. 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.

Botany/Equisetophyta – Wikibooks, open books for an open world

Morphology and evolution of vascular plants 3rd ed. In extinct groups, further protection was afforded to the spores by the presence of whorls of bracts – big pointed microphylls protruding from the cone. International Journal of Plant Sciences.

Equisetohyta with ‘species’ microformats All articles with unsourced statements Articles with unsourced statements from July Commons category link is on Wikidata. Plant systematics, a phylogenetic approach. 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.


Paleobotany and the evolution of plants 2nd ed. The extant horsetails are homosporous equiestophyta, but extinct heterosporous species such as Calamostachys casheana appear in the fossil record.

Retrieved from ” https: Morphology of Plants and Fungi 5th ed. The horsetails and their fossil relatives have long been recognized as distinct from other seedless vascular plants. Morphology of vascular plants Lower Groups. Views Read Edit View history. Wikimedia Commons has media related to Equisetopsida. Archived from the original PDF on New York and London: This contrasts with the seed plants, which grow from an apical meristem – i.


The Equisetales existed alongside the Sphenophyllalesbut diversified as that group disappeared into extinction, gradually dwindling in diversity to today’s single genus Equisetum. The spores bear characteristic elatersdistinctive spring-like attachments which are hygroscopic: 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.

Equisetopsidaor Sphenopsidais a class of vascular plants with a fossil record going back to the Devonian. Data related to Equisetopsida at 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. Developmental morphology and fuzziness of organ equistophyta. Recent phylogenetic analysis has produced evidence that this group equisetophuta plants belongs firmly within the fern clade of vascular plants. There were three orders of Equisetopsid; the Pseudobornialeswhich first appeared in the late Devonian.

Evolution of horsetails Equisetales within the major euphyllophyte clade Sphenopsida”.

Equisetopsida – Wikipedia

The extant horsetails represent a tiny fraction of Sphenophyte diversity in the past. The biology and evolution of fossil plants. Charophytes non-basal Charophyceae Divisioon Zygnematophyceae Mesotaeniaceae. The Origin and early diversification of land plants: American Journal of Botany.