Equisetidae

See also: Equisetopsida sensu lato

Equisetidae
Temporal range: Late Devonian[1] to Recent
An erect plant with unbranched segmented stems. Whorls of small leaves sprout from each segment, thicker at the top end and absent in the lower portion of the stem, giving it the appearance of a bottle brush or a horse's tail.
Equisetum telmateia
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Division: Polypodiophyta
Class: Polypodiopsida
Subclass: Equisetidae
Warm.
Orders
Synonyms

See text.

Equisetidae is one of the four subclasses of Polypodiopsida (ferns), a group of vascular plants with a fossil record going back to the Devonian. They are commonly known as horsetails.[2] They typically grow in wet areas, with whorls of needle-like branches radiating at regular intervals from a single vertical stem.

The Equisetidae were formerly regarded as a separate division of spore plants and called Equisetophyta, Arthrophyta, Calamophyta or Sphenophyta. When treated as a class, the names Equisetopsida s.s. and Sphenopsida have also been used. They are now recognized as rather close relatives of the ferns (Polypodiopsida) of which they form a specialized lineage.[3] However, the division between the horsetails and the other ferns is so ancient that many botanists, especially paleobotanists, still regard this group as fundamentally separate at the higher level.

  1. ^ Cite error: The named reference TaylTayl93 was invoked but never defined (see the help page).
  2. ^ Cite error: The named reference PPGI was invoked but never defined (see the help page).
  3. ^ Cite error: The named reference SmitPryeSchuKora06 was invoked but never defined (see the help page).