Salicaceae

Salicaceae
Temporal range: Eocene - recent[1]
Salix alba
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Rosids
Order: Malpighiales
Family: Salicaceae
Mirb.[2]
Subfamilies[3]
Synonyms
The image shows a drawing of a small portion of the edge of a leaf bearing a salicoid tooth. Black veins cross the leaf surface, but one vein is marked yellow and widens as it approaches the tooth. At the tip of the tooth is a semicircular protuberance, also drawn as yellow for emphasis.
Illustration of a typical salicoid tooth, the yellow area showing the expanding leaf vein and glandular seta.
The image is a photograph of the edge of the underside of a leaf. The leaf takes up the upper two-thirds of the image and the leaf margin runs right to left, with a single tooth jutting out bluntly to the left. Also sporadically along the edge of the leaf are small, transparent hairs. The light-colored leaf surface is intersected with dark veins, one of which comes in from the top right of the image towards the tooth, and it widens abruptly as it nears the tooth. Between the tip of the tooth and where it steps down to the next part of the leaf margin is a shallow bulge with a brownish hue, a distinctly different color from the rest of the leaf. A red scale bar at upper left, occupying about a quarter of the width of the image, above which reads "0.5 mm."
Populus trichocarpa leaf margin showing a salicoid tooth. The brownish-yellow area in the axil of the tooth is the glandular seta.

The Salicaceae are the willow family of flowering plants. The traditional family (Salicaceae sensu stricto) included the willows, poplars. Genetic studies summarized by the Angiosperm Phylogeny Group (APG) have greatly expanded the circumscription of the family to contain 56 genera and about 1220 species, including the tropical Scyphostegiaceae and many of the former Flacourtiaceae.[4][5][6]

In the Cronquist system, the Salicaceae were assigned to their own order, Salicales, and contained three genera, Salix, Populus, and Chosenia (now a synonym of Salix). Recognized to be closely related to the Violaceae and Passifloraceae, the family is placed by the APG in the order Malpighiales.

Under the new circumscription, most members of the family are trees or shrubs that have simple leaves with alternate arrangement, and temperate members are usually deciduous. Most members have serrate or dentate leaf margins, and many of those that have such toothed margins exhibit salicoid teeth, a salicoid tooth being one in which a vein enters the tooth, expands, and terminates at or near the apex, near which are spherical and glandular protuberances called setae. Sometimes the glands will deflate and appear torus (doughnut) shaped. Some members of the family exhibit violoid or theoid teeth, characters along with presence of an aril and introrse anther dehiscence that are sometimes used to split the family into three families, Salicaceae sensu medio, Samydaceae, and Scyphostegiaceae.[7][8] Members of the family often have flowers which are reduced and inconspicuous, and all have ovaries that are superior or half-inferior with parietal placentation.[9]

  1. ^ "Malpighiales". www.mobot.org. Retrieved 2023-06-16.
  2. ^ "Salicaceae Mirb., nom. cons". Germplasm Resources Information Network. United States Department of Agriculture. 2003-01-17. Retrieved 2010-02-04.
  3. ^ Stevens, P.F. (2015) [1st. Pub. 2001], Angiosperm Phylogeny Website, retrieved 28 January 2021
  4. ^ Chase, Mark W.; Sue Zmarzty; M. Dolores Lledó; Kenneth J. Wurdack; Susan M. Swensen; Michael F. Fay (2002). "When in doubt, put it in Flacourtiaceae: a molecular phylogenetic analysis based on plastid rbcL DNA sequences". Kew Bulletin. 57 (1): 141–181. Bibcode:2002KewBu..57..141C. doi:10.2307/4110825. JSTOR 4110825.
  5. ^ Christenhusz, M. J. M. & Byng, J. W. (2016). "The number of known plants species in the world and its annual increase". Phytotaxa. 261 (3). Magnolia Press: 201–217. doi:10.11646/phytotaxa.261.3.1.
  6. ^ Stevens, P. F. (2001 onwards). Angiosperm Phylogeny Website. Version 9, June 2008 (and more or less continuously updated since).
  7. ^ Samarakoon, T., and M.H. Alford. 2019. New Names and Combinations in Neotropical Samydaceae Novon 27: 65-71.
  8. ^ Wurdack, K.J., and C.C. Davis. 2009. Malpighiales phylogenetics: Gaining ground on one of the most recalcitrant clades in the angiosperm tree of life American Journal of Botany 96: 1551-1570.
  9. ^ Judd, Walter S. (January 2015). Plant systematics : a phylogenetic approach (Fourth ed.). Sunderland, MA. ISBN 978-1-60535-389-0. OCLC 920680553.{{cite book}}: CS1 maint: location missing publisher (link)