Asplenium unisorum

Asplenium unisorum
Conservation status
Critically Endangered  (IUCN 3.1) [1]
Endangered  (ESA) [2] [3]
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Division:	Polypodiophyta
Class:	Polypodiopsida
Order:	Polypodiales
Suborder:	Aspleniineae
Family:	Aspleniaceae
Genus:	Asplenium
Species:	A. unisorum
Binomial name
Asplenium unisorum (Wagner) Viane [4]
Synonyms [4]
Diellia unisoraWagner

Asplenium unisorum, the singlesorus island spleenwort, ^[5] is a species of fern endemic to the Hawaiian Islands. ^[1] It only lives between 650 and 700 m in the Wai'anae Mountains on the island of O'ahu. ^[1] It is classified as critically endangered, with a fragmented, actively shrinking mature population of around 1,148. ^[1]

Description

It grows 0.5-3.0cm tall, with a 0.5-1.0cm diameter. ^[6] Leaf stalks branch off the main stem, which also features a few "small black scales". ^[6] The stalks themselves are "black and shiny", around 2.0-5.0cm long. ^[6] Branching off from the stalks, the fronds of the fern are 8.0-30.0cm tall by 0.5-3.0cm broad. ^[6]

References

1. Keir, M.; Sugii, N.; Gon, S.M.; Chau, M.; Kwon, J.; Weisenberger, L. (2017) [errata version of 2016 assessment]. "Asplenium unisorum". IUCN Red List of Threatened Species . 2016: e.T78775516A115493966. doi: 10.2305/IUCN.UK.2016-1.RLTS.T78775516A78775751.en .
2. "No common name (Asplenium unisorum)". Environmental Conservation Online System. U.S. Fish & Wildlife Service. Retrieved 20 June 2024.
3. "Endangered and Threatened Wildlife and Plants; Endangered Status for Three Plants From the Waianae Mountains, Island of Oahu, HI". Federal Register. 59 (122): 32932–32938.
4. "Asplenium unisorum (Wagner) Viane)". Global Biodiversity Information Facility . Retrieved 1 January 2025.
5. "Asplenium unisorum (W.H. Wagner) Viane". Integrated Taxonomic Information System . Retrieved 20 June 2024.
6. "Singlesorus Island Spleenwort". U.S. Fish & Wildlife Service. Retrieved 2025-02-25.