Asplenium haughtonii, also known as the Barn fern, is a species of fern in the family Aspleniaceae. It is native to Saint Helena.[3][2]

Asplenium haughtonii
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Division: Polypodiophyta
Class: Polypodiopsida
Order: Polypodiales
Suborder: Aspleniineae
Family: Aspleniaceae
Genus: Asplenium
Species:
A. haughtonii
Binomial name
Asplenium haughtonii
(Hook.) Bir, Fraser-Jenk. & Lovis[2]
Synonyms[2]
  • Ceterach haughtonii (Hook.) Cronk
  • Gymnogramma haughtonii Hook.

Taxonomy edit

A global phylogeny of Asplenium published in 2020 divided the genus into eleven clades,[4] which were given informal names pending further taxonomic study. A. haughtonii belongs to the "A. cordatum subclade" of the "Schaffneria clade".[5] The Schaffneria clade has a worldwide distribution, and members vary widely in form and habitat.[6] There is no clear morphological feature that unites the A. cordatum subclade. The sister species of A. haughtonii is A. phillipsianum from Socotra, and the two together are sister to the African A. cordatum. These three are scaly ferns of dry habitats; the other two species in the subclade are sister to them, and are walking ferns, with long undivided leaves and proliferating leaf tips.[7]

Etymology edit

The English name Barn fern is derived from a basalt hill located on the north-east of Saint Helena called The Barn. This hill is believed to carry 60% of the entire A. haughtonii population.[3]

Distribution edit

They are found at elevations of 250–600 m. It is found on the drylands of the island. It is widely distributed, although they are usually found in remote areas.[3]

Status edit

It is listed as critically endangered by the IUCN.[3]

Threats edit

In 2012, an emergency extension area to a runway of St Helena airport caused massive destruction of the species' habitat. Before this event, individuals were abundant in Dry Gut which comprised a large majority of the world population.[3][8]

Conservation edit

Before the development of this extension occurred, some conservationists rescued as many individuals as possible for relocation. About 1,000 individuals were moved into the St Helena Government's Endemic Plant Nursery.[3][8]

References edit

  1. ^ "IUCN Red List of Threatened Species: Asplenium haughtonii". 12 June 2015.
  2. ^ a b c "Asplenium haughtonii (Hook.) Bir, Fraser-Jenk. & Lovis | Plants of the World Online | Kew Science". Plants of the World Online. Retrieved 2020-10-26.
  3. ^ a b c d e f Phil Lambdon (St. Helena Nature Conservation Group/ Royal Botanic Gardens, Kew); Assessments), Shayla Ellick (St Helena Plant (2015-06-12). "IUCN Red List of Threatened Species: Asplenium haughtonii". IUCN Red List of Threatened Species. Retrieved 2020-10-26.
  4. ^ Xu et al. 2020, p. 27.
  5. ^ Xu et al. 2020, p. 36.
  6. ^ Xu et al. 2020, p. 42.
  7. ^ Xu et al. 2020, pp. 43–44.
  8. ^ a b "Endemic Species | Saint Helena Island Info: All about St Helena, in the South Atlantic Ocean". sainthelenaisland.info. Retrieved 2020-10-26.