Hesperomannia oahuensis
Names
- ʻŌlelo Hawaiʻi: n/a
- Scientific: Hesperomannia oahuensis
Conservation Status
- Federal and State Listed as Endangered
- Plant Extinction Prevention Program Target
- IUCN Red List Ranking ‐ CR A2ac; B1ab(iii,v); C1+2a(i); D
- Hawai‘i Natural Heritage Ranking ‐ Critically Imperiled (G1)
- Endemism – O‘ahu, Maui
- Critical Habitat ‐ Designated
Species Information
Hesperomannia oahuensis, a member of the aster family (Asteraceae), is endemic to the Waianae Mountains on O’ahu. There are fewer than ten plants remaining in the wild. Hesperomannia oahuensis is a small shrubby tree, 2 to 3.3 m, (7 to 11 ft) tall. Leaves are elliptic, generally 10 to 18 cm (4 to 7 in) long and 5.5 to 11.5 cm (2.2 to 4.5 in) wide, although leaves on juvenile plants can sometimes be larger. Flower heads are erect and arranged in clusters of four or five heads. This species can be distinguished from other members of the genus by the erect flower heads and the leaves, usually hairy beneath, which are one to two times as long as wide. Historically, Hesperomannia oahuensis is known from the central and southern Wai‘anae Mountains from Makaleha to Pu‘u Kanehoa, and from West Maui.
Distribution
The 6-10 remaining plants all live within two populations in the Wai’anae Mountains n O’ahu (“5-Year Review: Short Form Summary,” 2013).
Habitat
Mixed mesic forests on steep slope of the Waianae Mountains.
Threats
- Fire
- Competition with alien invasive plants
- Consumption by rats and feral ungulates
References & Additional Resources
For more information and references visit the State Wildlife Action Plan factsheets. DOFAWʻs species pages and State Wildlife Action Plan fact sheets are provided for general information and are not meant to be a citable, original source of data. If you are a student, researcher, or writer looking for a citable source, please explore the references below or find other original data sources, rather than citing these webpages. The references below were provided by the authors of the State Wildlife Action Plan fact sheets at the time of drafting:
Hawai‘i Natural Heritage Program. 2005. Hawaii Natural Heritage Program Search, https://www.hinhp.org.
International Union for Conservation of Nature and Natural Resources, 2004, IUCN Red List of Threatened Species: Data Base Search, https://www.redlist.org/search/search‐basic.html.
US Fish and Wildlife Service. 1991. Final Listing, Endangered ETWP; Determination of Endangered Status for 26 Plants from the Waianae Mountains, Island of Oahu, Hawaii; Federal Register, Vol. 56, No. 209, (29‐OCT‐91) 56 FR 55770‐55786, 17 pp.
Wagner, W. L., D. R. Herbst, and D. H. Lorence. 2005. Flora of the Hawaiian Islands website. https://ravenel.si.edu/botany/pacificislandbiodiversity/hawaiianflora/index.htm [August, 2005].
Wagner, W.L., Herbst, D.R., and Sohmer, S.H., 1999. Manual of the flowering plants of Hawaiʹi‐‐ Revised Edition. Honolulu, HI: University of Hawaii Press and Bishop Museum Press. 1853p.
“5-Year Review: Short Form Summary.” United States Fish and Wildlife Service, 2013.
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