Polygonum smallianum (synonym Polygonella macrophylla)[1] is a species of flowering plant in the knotweed family known by the common name largeleaf jointweed. It is native to a small area around the border between Alabama and Florida in the United States.[2][3]

Polygonum smallianum

Vulnerable  (NatureServe)
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Order: Caryophyllales
Family: Polygonaceae
Genus: Polygonum
Species:
P. smallianum
Binomial name
Polygonum smallianum
Synonyms[1]
  • Polygonella macrophylla Small

Description edit

This plant is a perennial herb or subshrub with stiff, erect stems coming from a woody base and taproot. It may exceed one meter in height. The leathery leaves are alternately arranged. The largest near the stem bases are up to 6.8 centimeters long. They are mostly oval with smooth edges and rounded tips. The inflorescence is made up of a number of racemes of flowers. There is a white- or pinkish-flowered form and a red-flowered form.[3][4][5]

Taxonomy edit

The species was first described in 1856 by John Kunkel Small as Polygonella macrophylla.[6] In 2015, following a series of molecular phylogenetic studies, the genus Polygonella was subsumed into Polygonum.[7][8] However, the name "Polygonum macrophylla" was unavailable, so the replacement name Polygonum smallianum was published in 2011.[7][9]

Distribution, habitat and conservation edit

This species occurs in the Florida scrub of the Florida Panhandle and a part of southern Alabama. It grows in open scrub and coastal dunes. Rare in general, it can be common in its range.[2][3]

The main threat to the species is the loss of its scrub habitat to development and silviculture.[2][3]

References edit

  1. ^ a b c "Polygonum smallianum T.M.Schust. & Reveal". Plants of the World Online. Royal Botanic Gardens, Kew. Retrieved 2019-02-28.
  2. ^ a b c Polygonella macrophylla. Archived 2011-10-26 at the Wayback Machine Center for Plant Conservation.
  3. ^ a b c d Polygonella macrophylla. The Nature Conservancy.
  4. ^ Polygonella macrophylla. Flora of North America.
  5. ^ Lewis, P. O. (1991). Allozyme variation in the rare Gulf Coast endemic Polygonella macrophylla Small (Polygonaceae). Plant Species Biology 6(1) 1-10.
  6. ^ "Plant Name Details for Polygonella macrophylla Small". The International Plant Names Index. Retrieved 2019-02-28.
  7. ^ a b Schuster, T.M.; Reveal, J.L. & Kron, K.A. (2011). "Evolutionary Relationships within Polygoneae (Polygonaceae: Polygonoideae)". Taxon. 60: 1653–1666. doi:10.1002/tax.606010., cited in Schuster et al. (2015)
  8. ^ Schuster, Tanja M.; Reveal, James L.; Bayly, Michael J. & Kron, Kathleen A. (2015). "An updated molecular phylogeny of Polygonoideae (Polygonaceae): Relationships of Oxygonum, Pteroxygonum, and Rumex, and a new circumscription of Koenigia". Taxon. 64 (6): 1188–1208. doi:10.12705/646.5.
  9. ^ "Plant Name Details for Polygonum smallianum T.M.Schust. & Reveal". The International Plant Names Index. Retrieved 2019-02-28.