Ha'iwale (Cyrtandra viridiflora)

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Ha'iwale

Cyrtandra viridiflora

StatusEndangered
ListedOctober 10, 1996
FamilyGesneriaceae (African violet)
DescriptionThick, fleshy, heart-shaped leaves with long, velvety, pale hairs and one to five green flowers.
HabitatWind-blown ridge tops in cloud-covered wet forest or shrubland.
ThreatsDegradation or destruction by feral pigs, potential impacts from military activities, potential predation by rats, and competition with the alien plants.
RangeHawaii

Description

Cyrtandra viridiflora is a small shrub of the African violet family that reaches 1.6-6.6 ft (48.8-201.2 cm) in height. The thick, fleshy, heart-shaped leaves are 2.4-6 in (6.1-15.2 cm) long, 1.4-3.0 in (3.6-7.6 cm) wide, and have toothed margins. Both the upper and lower surfaces have long, velvety, and pale hairs. One to five green flowers are arranged on an inverse umbrella-shaped flowering stalk. The pale green calyx is 0.5-0.6 in (1.3-1.5 cm) long; the round, white berries are 0.5 in (1.3 cm) or longer. This species is distinguished from others in the genus by its thick, fleshy, and heart-shaped leaves that are densely hairy on both surfaces.

Harold St. John and W. B. Storey first described C. viridiflora in 1950 from a specimen collected by Joseph Rock in 1911. Other published names now considered synonyms of this species are Cyrtandra crassifolia and C. pickeringii var. crassifolia. The specific epithet refers to the conspicuous green flowers.

Habitat

C. viridiflora is usually found on wind-blown ridge tops in cloud-covered wet forest or shrubland at elevations of 2,260-2,800 ft (689-853 m) Associated plant taxa include kanawao, 'ohi'a, 'ohi'a ha, 'uki, and uluhe.

Distribution

C. viridiflora was known historically from seven scattered populations in the Koolau Mountains on the island of Oahu. Now known from only four populations in the northern Koolau Mountains, this species occurs on state and private land leased by the Department of Defense for Kawailoa Training Area at Kawainui-Laie summit divide, Kawainui-Kaipapau summit divide, Maakua-Kaipapau Ridge, and the Peahinaia Trail. The total number of plants growing in 1998 at these four locations was about 21.

Threats

The major threats to C. viridiflora are habitat degradation or destruction by feral pigs, potential impacts from military activities, potential predation by rats, competition with the alien plants Koster's curse and strawberry guava, and risk of extinction from naturally occurring events. Additionally the species is at risk from reduced reproductive vigor due to the small number of remaining populations and individuals.

It is possible that rats eat the fruit of C. viridiflora, a plant with fleshy stems and fruit that grows in areas where rats occur.

The noxious shrub Koster's curse is a threat to C. viridiflora; dense stands formed by strawberry guava are also a major threat.

Populations of C. viridiflora that occur on land leased and owned by the U.S. Army face the threat of being damaged through military activity, either by troops in training maneuvers or by the construction, maintenance, and utilization of helicopter landing and drop-off sites.

Conservation and Recovery

The Lyon Arboretum is propagating C. viridiflora.

Contact

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
http://pacific.fws.gov/

Reference

U.S. Fish and Wildlife Service. 1998. "Recovery Plan for Oahu Plants." U.S. Fish and Wildlife Service, Portland.