Alani (Melicope reflexa)

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Alani

Melicope reflexa

StatusEndangered
ListedOctober 8, 1992
FamilyRutaceae (Citrus)
DescriptionSprawling yellowish-brown shrub of the citrus family.
HabitatWet 'ohi'a-dominated forests.
ThreatsDisturbance, predation by feral or domestic animals.
RangeHawaii

Description

This alani (Melicope reflexa ), a sprawling shrub of the citrus family, attains a height of 3.3-10 ft (1-3 m) and has short, yellowish-brown, short-lived cilia on new growth. The elliptical leathery leaves are opposite and thin, measuring 3.1-5.1 in (7.9-13 cm) long and 1.6-2.8 in (4.1-7.1 cm) wide. The flowers are observed singly or in clusters of two or three from the leaf axil. The flower cluster has a stalk measuring 0.1-0.6 in (2.5-15.2 mm) long, and each flower is on a 0.6-0.8-in-long (1.5-2-cm-long) stalk. Male flowers have not been observed, but the female flowers are made up of four overlapping sepals; four petals; an eight-lobed nectary disk; eight reduced, nonfunctional stamens; and a style about 0.2 in (5.1 mm) long. The capsules are 0.8-1.3 in (2-3.3 cm) wide with four sections that are fused to each other along about one-fourth of their length. One or two glossy black seeds are found in each section of the capsule.

Habitat

M. reflexa typically grows in wet 'ohi'a-dominated forests with native trees such as 'olapa at elevations of 2,490-3,900 ft (759-1,189 m).

Distribution

Historically, M. reflexa occurred on East Molokai from a ridge between Hanalilolilo and Pepeopae in Kamakou Preserve to as far east as Halawa.

The three remaining populations of fewer than 1,000 total plants are distributed over a distance of 7.5 mi (12 km) of private land at the headwall of the Waikolu Valley on Wailau-Mapulehu summit, Kukuinui Ridge, and Honomuni.

Threats

Because it is confined to one restricted area, M. reflexa is highly susceptible to stochastic extinction or predation by feral or domestic animals. The plant fauna of Molokai has currently fallen vulnerable to 1) habitat degradation and/or predation by axis deer, goats, pigs, sheep, and cattle; 2) competition for space, light, water, and nutrients by naturalized, exotic species; 3) habitat loss due to fires; 4) predation by rats; 5) damage caused by human recreational activities; and 6) injury incurred during military exercises. Overgrazing by axis deer and goats has irreparably damaged much native vegetation of Molokai and Hawaii. These feral animals graze to the point of exposing the soil to erosion. Eight axis deer were introduced to Molokai in 1868 and flourished to thousands by 1960. Goats were also introduced to the island in the 1800s, anddespite the goatskin tradethey managed to invade the high-elevation dry forests and are now invading the wetter regions along the northern coast of East Molokai. Feral pigs inhabit the wetter forested regions of Molokai in the Molokai Forest Reserve. These pigs root, trample, and degrade native vegetation and habitat.

Cattle ranching on Molokai has played a significant role over most of the past 150 years in reducing areas of native vegetation to vast pastures of alien grasses. In 1960 about 61% of Molokai's landsprimarily in the western and central sections of the islandwere devoted to grazing. Cattle degrade the habitat by trampling and feeding on vegetation, eventually exposing the groundcover and increasing soil vulnerability to erosion. Red erosional scars resulting from decades of cattle disturbance (and exacerbated by other feral ungulate activities) are still evident on West Molokai and the upper elevations of East Molokai. Cattle facilitate the spread of alien grasses and other plants.

Cattle ranching was succeeded in the 1920s by pineapple cultivation. Most of the land used for this agricultural activity had already been altered through the decades of cattle ranching. However, pineapple cultivation contributed to a high degree of erosion until its decline in the 1970s.

Conservation and Recovery

Alteration of vegetation limits natural areas. The Molokai Forest Reserve, located on the upper elevation mesic to wet forests of East Molokai, is the single designated protected area on the island. This reserve accounts for 30% of Molokai's land area.

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/

Pacific Remote Islands Ecological Services Field
Office
300 Ala Moana Blvd., Room 3-122
P.O. Box 50088
Honolulu, Hawaii 96850
Telephone: (808) 541-1201
Fax: (808) 541-1216

Reference

U. S. Fish and Wildlife Service. 8 October 1992. "Endangered and Threatened Wildlife and Plants; Determination of Endangered or Threatened Status for 16 Plants from the Island of Molokai, Hawaii." Federal Register 57 (196): 46325-46339.

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