Alani (Melicope adscendens)

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Alani

Melicope adscendens

StatusEndangered
ListedDecember 5, 1994
FamilyRutaceae (Citrus)
DescriptionA tropical shrub.
HabitatHumid tropical forest.
ThreatsHabitat destruction and browsing by introduced mammalian herbivores.
RangeHawaii

Description

The alani (Melicope adscendens ) is a shrub with long, slender, sprawling branches that are covered with fine, yellowish to golden brown or gray hairs when young, but becoming smooth when older. The leaves are arranged in opposite fashion on the stems, and are widely spaced, leathery to papery in texture, elliptical in shape, and hairless. The leaves are 0.6-2.6 in (1.5-6.5 cm) long and 0.4-1.6 in (1-4 cm) wide, with a petiole 0.2-0.6 in (0.6-1.6 cm) long. The flowers are on individual stalks 0.2-0.3 in (4-8 mm) long, and occur in clusters of one to three on a main stalk 0.5-0.7 in (13-17 mm) long. Only female flowers have been observed. These have four sepals about 0.1 in (3.5 mm) long, four petals about 0.2 in (5 mm) long, an eight-lobed nectary disk (this secretes nectar to attract pollinator insects), eight reduced and non-functional stamens, and a four-celled ovary. When mature, the fruit is about 0.6 in (14-15 mm) wide, and is made up of four follicles (dry fruits that split along one side). The sepals and petals remain attached to the mature fruit. The endocarp (inner fruit wall) and the wrinkled exocarp (outer fruit wall) are both hairless.

The alani is pollinated by insects, which are attracted by nectar-secreting glands in the flowers. The means of dispersal of the seeds is not known.

Habitat

The alani occurs in moist, lowland, tropical forest dominated by the native trees olopua (Nestegis sandwicensis ) and hala pepe (Pleomele auwahiensis ).Most of the original area of this natural forest community has been converted into pasture, and the remnants now survive as scattered patches. This community occurs at elevations of 100-5,250 ft (30-1,600 m). The rainfall is seasonal, mostly occurring from October to March, and the soil is well-drained.

Distribution

The alani is an endemic (or locally evolved) species that only occurs on the southwestern slopes of the volcanic mountain Haleakala, on the island of Maui, in the Hawaiian Islands. The Hawaiian archipelago has an extremely large fraction of endemic species in its flora; about 89% of the indigenous flowering plants occur nowhere else.

Threats

Only two plants of the alani were found by a botanist in 1920. In the later 1990s, one of these same plants still existed near Puu Ouli on privately owned land; the other plant had not been relocated. The known plant grows beside a water pipeline on land used as a cattle pasture. It is threatened by damage potentially associated with pipeline maintenance, trampling by cattle, competition with the alien plants lantana (Lantana camara ) and Kikuyu grass (Pennisetum clandestinum ), and reduced reproductive vigor and/or extinction caused by an accidental disturbance (such as a fire or hurricane). It is also potentially threatened by non-native deer, pigs, and insects.

Conservation and Recovery

The endangered alani is a protected species, and it cannot be deliberately damaged, collected, or sold without a permit. The only known surviving individual of the alani is located on privately owned land. The landowner has been notified of the importance of protecting this rare species and its habitat. However, this individual should be enclosed within a fenced-off area to protect it from mammalian herbivores, and its habitat declared an ecological reserve. Research should be undertaken to find ways of propagating the critically endangered alani, to provide stock for out-planting into suitable wild habitat.

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 Islands Office
U. S. Fish and Wildlife Service
300 Ala Moana Boulevard, Room 6307
P. O. Box 50167 Honolulu,
Hawaii 96850

Reference

U. S. Fish and Wildlife Service. 5 December 1994. "Endangered and Threatened Wildlife and Plants; Endangered Status for Three Hawaiian Plant Species of the Genus Melicope." Federal Register 59(232):62346-62352.