'Oha Wai (Clermontia drepanomorpha)
|Listed||October 10, 1996|
|Description||Terrestrial branching tree; bears stalked leaves, flowers, and orange berries.|
|Habitat||Montane wet forests.|
|Threats||Ditch improvements; competition from alien plant taxa; habitat disturbance by feral pigs; girdling of the stems by rats.|
Clermontia drepanomorpha, the 'oha wai, is a member of the bellflower family (Campanulaceae), a terrestrial or epiphytic (not rooted in the soil), branching tree 8.2-23 ft (2.5-7 m) tall. The stalked leaves are 4-11 in (10.2-28 cm) long and 0.6-1.8 in (1.5-4.5 cm) wide. Two to four flowers, each with a stalk 0.8-1.4 in (2-3.5 cm) long, are positioned at the end of a main flower stalk 2-5 in (5-12.7 cm) long. The calyx (fused sepals) and corolla (fused petals) are similar in size and appearance, and each forms a slightly curved, five-lobed tube 1.6-2.2 in (4-5.6 cm) long and 0.6-0.8 in (1.5-2 cm) wide which is blackish purple. The berries are orange and 0.8-1.2 in (1.5-3 cm) in diameter. This species is distinguished from others in this endemic Hawaiian genus by similar sepals and petals, the long drooping inflorescence, and large blackish purple flowers.
Joseph F. Rock (1913) named C. drepanomorpha on the basis of specimens collected in the Kohala Mountains of the island of Hawaii in the early 1900s.This taxonomy was retained in the latest treatment of the genus.
This species typically grows in Metrosideros polymorpha ('ohi'a), Cheirodendron trigynum ('olapa), and Cibotium glaucum (hapu'u) dominated montane wet forests, often epiphytically, at elevations between 3,850 and 5,150 ft (1,174 and 1,570 m). Associated taxa include Carex alligata, Melicope clusiifolia (alani), Styphelia tameiameiae (pukiawe), Astelia menziesii (pa'iniu), Rubus hawaiiensis ('akala), Cyanea pilosa (haha), and Coprosma sp. (pilo).
Historically, C. drepanomorpha was known from four populations in the Kohala Mountains on the island of Hawaii. Only 13-20 individuals in two populations, bordering private ranch lands, were known to be extant until recent surveys. In 1995, the U.S. Fish and Wildlife Service contracted with the National Tropical Botanical Garden (NTBG) to conduct a thorough survey of the Kohala area. Approximately five populations totaling 200 individuals of C. drepanomorpha were found within a 5-mi (8-km) state-owned area of the only remaining habitat for the species.
The major threats to C. drepanomorpha are ditch improvements, competition from alien plant taxa, like thimbleberry, habitat disturbance by feral pigs, girdling of the stems by rats, and a risk of extinction from naturally occurring events (such as hurricanes) and/or reduced reproductive vigor due to the small number of existing populations.
Conservation and RecoveryAs of May 1998, there are 48 plants at the Volcano Rare Plant Facility. The NTGB has 50 seeds in storage, but the viability is unknown. Lyon Arboretum contains 13 separate tissue culture associations and 90 plants from tissue culture. They also have five greenhouse 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. 1998. "Big Island II: Addendum to the Recovery Plan for the Big Island Plant Cluster." U.S. Fish and Wildlife Service, Portland, Oregon. 80 pp. + appendices.