'Akoko (Chamaesyce kuwaleana)
|Listed||October 29, 1991|
|Description||Shrub with reddish-brown young bark; untoothed, oval leaves; and flower clusters in leaf axils.|
|Habitat||Arid volcanic cliffs.|
|Threats||Alien plant species and low numbers.|
Chamaesyce kuwaleana is an erect shrub of the spurge family that grows to a height of 36 in (91 cm). Young bark is reddish-brown; older bark is dark gray. The untoothed leaves, which have a whitish waxy coating on the upper surface, are oval to circular and are arranged in two rows along the stem. Flower clusters appear at the leaf axils.
C. kuwaleana is found on arid volcanic cliffs in the Waianae Mountain Range at elevations of 600-1,050 ft (182.9-320 m). Associated vegetation includes ilima (Sida fallax ) and 'a'ali'i (Dodonaea viscosa ). C. kuwaleana bears fruits in spring and early summer and is usually done fruiting by the fall. This species has also been known as Euphorbia kuwaleana.
C. kuwaleana was first described in 1949. The species was known historically from the central Waianae Mountains and Moku Manu Island off the eastern coast of Oahu. The three populations known in 1997 occurred 3 mi (4.8 km) apart on federal and state land and contained approximately 2,000 individuals. Kauaopuu Peak had two populations with about 500 and 1,000 individuals, respectively, and Puu Kailio had a single population of several hundred individuals.
As with other rare native Hawaiian plant species, the major threat to C. kuwaleana is competition from alien plant species. It is directly threatened by koa haole, an aggressive tree that colonizes disturbed lowland shrubland.
The low number of known plants and their limited distribution make the species vulnerable to extinction through unpredictable human or natural events. Plants such as C. kuwaleana that inhabit dry habitats are especially susceptible to wildfires.
Conservation and Recovery
This species is being propagated at the National Tropical Botanical Garden. Specific efforts should be made to immediately weed and protect the remaining extant populations. A coordinated fire protection plan for endangered plant species on state (Waianae Kai Forest Reserve) and federal (Lualualei Military Reservation) lands needs to be developed and implemented.
U.S. Fish and Wildlife Service
Regional Office, Division of Endangered Species
Eastside Federal Complex
911 N.E. 11th Ave.
Portland, Oregon 97232-4181
Pacific Remote Islands Ecological Services Field Office
300 Ala Moana Blvd., Room 3-122
P.O. Box 50088
Honolulu, Hawaii 96850
Telephone: (808) 541-1201
Fax: (808) 541-1216
Cuddihy, L. W., and C. P. Stone. 1990. Alteration of Native Hawaiian Vegetation: Effects of Humans, Their Activities and Introductions. Cooperative National Park Resources Study Unit, University of Hawaii Press, Honolulu.
Stone, C. P., and J. M. Scott, eds. 1985. Hawaii's Terrestrial Ecosystems: Preservation and Management. Cooperative National Park Resources Study Unit, University of Hawaii Press, Honolulu.
Wagner, W. L., D. R. Herbst, and S. H. Sohmer. 1990. Manual of the Flowering Plants of Hawaii. University of Hawaii Press and Bishop Museum Press, Honolulu.