No Common Name
|Listed||October 29, 1991|
|Description||Prostrate, branched shrub with a peeling, corky bark and clusters of tubular flowers.|
|Threats||Feral pigs, alien plant species, low numbers.|
Hedyotis degeneri is a prostrate, branching shrub of the coffee family that has a four-sided stem and a peeling, corky bark. Leaf shapes are variable, ranging from long and thin to heart-shaped. Leafy shoots sprout from the leaf axils. Clusters of up to ten flowers appear at the ends of the stems. The flower petals are fused into a trumpet-shaped tube about 0.3 in (7.6 mm) long that ends in four or five lobes. The fruits are round capsules containing dark angled seeds. This species has been observed in flower in November, June, and July and in fruit in July.
Two varieties of H. degeneri are recognized: var. degeneri, which is the typical variety, and var. coprosmifolia, which has narrower leaves.
H. degeneri is found in diverse moist forest at an elevation of 2,700 ft (823 m). Associated plants include 'ohi'a (Metrosideros polymorpha ) and manono (H. terminalis ).
H. degeneri, first described in 1943, has been found only on Mt. Kaala and Kamaileunu Ridge in the Waianae Mountains of Oahu. The known populations on state-owned land totaled 32 individuals in 1997: six plants at Kamaileunu Ridge, 25 near Pahole Gulch, and one in Makaleha Valley.
The main threats to H. degeneri, as to most of the rare plant species of the Waianae Mountains, are habitat degradation by feral pigs and competition from aggressive alien plant species. With only 32 known surviving plants in three populations, the species is also extremely vulnerable to extinction through unpredictable natural or human-induced events.
Conservation and Recovery
This species is being successfully propagated at the National Tropical Botanical Garden and the Lyon Arboretum.
U. S. Fish and Wildlife Service
Regional Office, Division of Endangered Species
Eastside Federal Complex
911 N. E. 11th Ave.
Portland, Oregon 97232-4181
Telephone: (503) 231-6121
Pacific Remote Islands Ecological Services Field
300 Ala Moana Blvd., Room 3-122
P. O. Box 50088
Honolulu, Hawaii 96850
Telephone: (808) 541-1201
Fax: (808) 541-1216
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.