Alani (Melicope zahlbruckneri)

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Alani

Melicope zahlbruckneri

StatusEndangered
ListedOctober 10, 1996
FamilyRutaceae (Citrus)
DescriptionMedium-sized tree, squarish fruit, branching habit, large leaves.
HabitatMontane mesic forest.
ThreatsTwo-spotted leafhopper, competition from introduced grasses, volcanic activity, potential fruit damage by rats.
RangeHawaii

Description

Melicope zahlbruckneri, of the citrus family, is a medium-sized tree 33-40 ft (10-12 m) tall. New growth is covered with yellowish brown, fine, short, curly hairs. The opposite, stalked, elliptically oblong leaves are 2.4-9.5 in (6-24 cm) long and 1.6-4.9 in (4-12.5 cm) wide, with well-defined lateral veins. Clusters of two to five flowers have main flowering stalks 5.9-7.9 in (15-20 cm) long and each flower has a stalk about 0.2 in (0.4 cm) long. Female flowers consist of four sepals about 0.05 in (1.5 mm) long, four petals about 0.1 in (3 mm) long, an eight-lobed nectary disk, eight reduced and nonfunctional stamens, and a hairless four-celled ovary. Male flowers consist of four sepals 0.1 in (3.5 mm) long, four petals about 0.2 in (6 mm) long, and eight functional stamens in two whorls equal to or longer than the petals. The fruit is squarish, 0.4-0.5 in (1-1.3 cm) long, and 1.2 in (3 cm) wide. M. zahlbruckneri is distinguished from other species of the genus by its branching habit, large leaves, and very large, squarish capsules.

Based on a specimen he collected in 1911 in Kipuka Puaulu, on the island of Hawaii, Pelea zahlbruckneri was described in honor of Dr. A. Zahlbruckner, director of the Botanical Museum in Vienna. Pelea has since been submerged into Meli-cope, creating the combination M. zahlbruckneri.

Habitat

This species is found in koa-and 'ohi'a-dominated montane mesic forest at elevations of 3,920-4,265 ft (1,200-1,300 m). Associated taxa include pilo, a'e, mamaki, kopiko, olopua, naio, papala, several species of alani, ho'i'o, 'a'ali'i, and the introduced grasses, meadow ricegrass, Hilo grass, and Dallis grass.

Distribution

Historically, M. zahlbruckneri was known only from the island of Hawaii near Glenwood, in Kipuka Puaulu, and at Moaula in Kau. As of the late 1990s, the species was known to be extant only in Kipuka Puaulu, on land owned by Hawaii Volcanoes National Park, with 30-35 individuals remaining. The species was reproducing at this fenced site, and juvenile plants were present.

Threats

The major threats to M. zahlbruckneri are the two-spotted leafhopper; competition from introduced grasses (meadow ricegrass, Hilo grass, and Dallis grass); habitat change due to volcanic activity; potential fruit damage by rats; and a risk of extinction from naturally occurring events and/or reduced reproductive vigor due to the small number of individuals in the one remaining population.

Conservation and Recovery

Hawaii Volcanoes National Park has fenced Kipuka Puaulu and has undertaken weed control efforts. There has been some effort to trap rodents and the Hawaii Department of Agriculture is researching biocontrol agents for the two-spotted leaf hopper.

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. "Big Island II: Addendum to the Recovery Plan for the Big Island Plant Cluster." U. S. Fish and Wildlife Service, Portland, Oregon, 80 pp.