Ha'iwale (Cyrtandra crenata)

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Ha'iwale

Cyrtandra crenata

StatusEndangered
ListedMarch 28, 1994
FamilyGesneriaceae (African violet)
DescriptionShrub with few branches; tufted lanceshaped, toothed, hairless, wrinkled leaves; and dense clusters of three to seven white flowers covered with thick brown hair.
HabitatRavines or gulches in mesic to wet forests.
ThreatsExtinction due to the limited number of individuals.
RangeHawaii

Description

This ha'iwale (Cyrtandra crenata ) is a few-branched shrub in the African violet family (Gesneriaceae) that reaches a height of 3-7 ft (0.9-2.1 m). The leaves are arranged in whorls of three, tufted at the ends of the branches. The leaves, 4.7-11 in (11.9-27.9 cm) long and 1.6-3.1 in (4.1-7.9 cm) wide, are generally elliptic or lance-shaped and have toothed margins. The upper leaf surface is generally hairless and has a wrinkled texture; the lower surface has only sparse hairs. Dense clusters of three to seven white flowers, covered with thick brown hair, arise from the leaf axils. The calyx is bilaterally symmetrical, with the three upper lobes somewhat longer than the two lower lobes. The curved, funnel-shaped flowers, about 0.9 in (2.3 cm) long and 0.2 in (0.5 cm) wide, develop into fleshy, ellipsoid berries about 0.7 in (1.8 cm) long that contain numerous tiny seeds. The berries, as well as various other plant parts, are covered with short-stalked, brownish, and hemispherical glands. C. crenata is distinguished from other species in the genus by the combinations of its three-leaf arrangement, bilaterally symmetrical calyx, and brownish, hemispherical glands. This species was observed in flower in June of 1947.

Habitat

C. crenata typically grows in ravines or gulches in mesic to wet forests between elevations of 1,250-2,400 ft (381-731 m). Associated plants include 'ohi'a, uluhe, and 'uki.

Distribution

Historically, C. crenata was known from Waikane Valley along the Waikane-Schofield Trail in the Koolau Mountains; the only population known in recent times grew at the boundary of private and state lands below that trail only about 0.5 mi (0.8 km) from its historical location. This population, last observed in 1947, contains an unknown number of individuals, if it even survives at all.

Threats

The primary threats to C. crenata are habitat degradation and predation by pigs, suspected predation by rats and slugs, competition with invasive alien plants like Koster's curse and strawberry guava, and a risk of extinction from naturally occurring events. An additional threat of extinction results from reduced reproductive vigor due to the extremely low numbers of individuals and populations of this species.

Conservation and Recovery

Until a population can be located, no specific conservation measures can be undertaken for C. crenata.

Contacts

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/

Senior Resident Agent Office
U.S. Fish and Wildlife Service
300 Ala Moana Boulevard, Room 7-235
P.O. Box 50223
Honolulu, Hawaii 96850-5000
Telephone: (808) 541-2681
Fax: (808) 541-3062

Reference

U.S. Fish and Wildlife Service. 28 March 1994. "Endangered and Threatened Wildlife and Plants: Endangered Status for 11 Plant Species from the Koolau Mountain Range, Island of Oahu, HI." Federal Register 59 (59): 14482-14492.