No Common Name
|Listed||May 13, 1992|
|Description||Vine with flowers in clusters of three to six per leaf axil, petals fused into strongly curved tube with white or pale yellow corolla lobes and fruit of fleshy black nutlets.|
|Habitat||Coastal plains, upland slopes and mountain ranges and summits.|
|Threats||Predation by wild, feral, or domestic animals; fires, human recreational activities.|
Stenogyne kanehoana, a climbing vine in the mint family, has weakly four-angled stems that are pubescent and 3-6.5 ft (1-2 m) long. The thin leaves are oppositely arranged, narrowly ovate to oblong to ovate, densely pubescent, 4 in (10.2 cm) long, and 1.5 in (3.8 cm) wide.
The flowers are in clusters of three to six per leaf axil; the petals are fused into a strongly curved tube about 1-1.6 in (2.5-4 cm) long, white or pale yellow with short pink corolla lobes. The fruit consists of four fleshy black nutlets. This species generally flowers from February through March, but flowering depends on precipitation, and flowers have been noted from January to as late as April. Fruits mature within six weeks. The lifespan appears to be seven to 12 years.
S. kanehoana occurs under a canopy of mesic forest trees on a ridge leading to the summit of Puu Kanehoa in the Waianae Range.
S. kanehoana is known from the east ridge of Puu Kanehoa, near the summit of the ridge connecting Puu Kanehoa with Puu Hapapa to the north and Puu Kaua to the south in the Waianae Mountains. The last remnant population of two plants near the summit of Puu Kanehoa was found dead in 1997.
Although no S. kanehoana populations are known in the wild, some remnant individuals may occur. The major threats to those individuals are habitat degradation and competition for space, water, light, and nutrients by Koster's curse and other naturalized alien plants. The extremely small number of potential individual plants and their restricted distribution increases the potential for extinction from natural events. Other potential threats that have been suggested include fire and deforestation, but these probably are not serious present threats to the species. Feral pigs and hikers are also thought to be a threat to S. kanehoana.
Conservation and Recovery
S. kanehoana is being propagated at the National Tropical Botanical Garden. To prevent extinction of this species, propagation and protected cultivation should be expanded immediately if extant individuals are located. Enhancement of any remaining wild populations by outplanting should be conducted as soon as adequate propagated material becomes available, and fencing and weed control, as appropriate, are underway. Establishment of new populations within the historical range of S. kanehoana should be initiated in areas that are managed to minimize the impacts of feral ungulates and alien plants.
U.S. Fish and Wildlife Service
Regional Office, Division of Endangered Species
Eastside Federal Complex
911 N.E. 11th Ave.
Portland, Oregon 97232-4181
U.S. Fish and Wildlife Service. 13 May 1992. " Determination of Endangered Status for Stenogyne kanehoana (No Common Name), a Hawaiian Plant." Federal Register 57 (93): 20592-20595.