Ma'oli'oli

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Ma'oli'oli

Schiedea kealiae

StatusEndangered
ListedOctober 10, 1996
FamilyCaryophyllaceae (Pink)
DescriptionSubshrub with weakly ascending to sprawling stems and flowering stalks with numerous unisexual flowers in crowded clusters.
HabitatSteep slopes and cliff faces in dry remnant Erythrina sandwicensis (wiliwili) or aulu forest.
ThreatsCompetition with alien plants, predation by slugs and snails, fire, erosion, landslides.
RangeHawaii

Description

Schiedea kealiae, or ma'oli'oli, a member of the pink family (Caryophyllaceae), is a subshrub with weakly ascending to sprawling stems 0.7-1.6 ft (0.2-0.5 m) long that form loose clumps. The lower stems are smooth, while the upper stems and flowering stalk bear glands. The opposite leaves, 1.2-4 in (3-10.1 cm) long and 0.1-0.6 in (0.25-1.5 cm) wide, are lance-shaped to elliptic lance-shaped and conspicuously three-veined with a prominent midrib. The flowering stalk is 1.2-4.3 in (3-10.9 cm) long, with numerous unisexual and perfect flowers in crowded clusters. The green sepals of the male flowers are approximately 0.1 in (0.25 cm) long; at 0.06-0.09 in (0.15-0.23 cm) long, the sepals of the female flowers, are marginally shorter. The nectaries, about 0.02-0.04 in (0.05-0.1 cm) long, are inconspicuous. The capsular fruit is 0.08-0.1 in (0.2-0.25 cm) long. The species is distinguished from others of this endemic Hawaiian genus by the length of the sepals and nectaries and the flowering stalk exclusively with stalkless glands. This plant has been observed in flower from March through June.

S. kealiae appears to be long-lived, but there is no evidence of regeneration from seed under field consitions. Seedlings of S. kealiae, like those of other Schiedea species in mesic or wet sites, are apparently consumed by introduced slugs and snails, which have been observed feeding on S. membranacea, a mesic forest species from Kauai. Schiedea occurring in dry areas produce abundant seedlings following winter rains, presumably because dry areas have fewer alien consumers.

A specimen of S. kealiae was collected on Oahu in 1936 that was named for Kealia, its place of discovery. S. gregoriana is considered synonymous with S. kealiae by the authors of the current treatment of the family.

Habitat

S. kealiae is usually found on steep slopes and cliff faces at elevations from 200 to 1,000 ft (61-304.8 m) in dry remnant Erythrina sandwicensis (wiliwili) or aulu forest. Associated plant species include alahe'e, ko'oko'olau, koa haole, naio, and 'ilima.

Distribution

S. kealiae was known historically from the northern Waianae Mountains and one collection from the Palikea area, near the southern end of the same mountain range. Four populations are currently located on the cliffs above Dillingham Airfield and Camp Erdman and at Kaena Point at the northern end of the Waianae Mountains. These populations occur on private land; state land, including land leased by the Department of Defense for the Kaena Military Reservation; and Federal land on Dillingham Military Reservation. These four populations totaled between 300 and 500 plants in 1997.

Threats

The major threats to S. kealiae are predation by introduced slugs and snails, competition with alien plants like Christmas berry and koa haole, and risk of extinction from random natural events or through reduced reproductive vigor due to the small number of existing populations. The Kaena Point population is additionally threatened by naturally occurring rock slides and fire.

Fire is also a potential threat to this species, which occurs in dry or mesic habitats where seasonal conditions exist for the easy spread of fire. Erosion, landslides, and rockslidesepisodes of land slippage caused by natural weathering and human modification of water runoff that can destroy individual plants and damage habitatpotentially threaten the Kaena Point population of S. kealiae.

Conservation and Recovery

S. kealiae is being successfully propagated at the National Tropical Botanical Garden and the Waimea Arboretum.

Control of introduced snails and slugs is essential for the protection of this species. S. kealiae reproduces prolifically under greenhouse conditions; therefore, the lack of seedlings in the field is almost certainly the result of grazing alien snails and slugs, which have been observed to consume seeds of related species and probably a substantial portion of their seed crop. Methods to control mollusk predation need to be found and implemented.

Research on pollinators is necessary because of the possibility that declines in native pollinator fauna might increase levels of inbreeding and result in the expression of inbreeding depression. Estimates on inbreeding depression for S. kealiae are not available.

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
(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, Oregon. 207 pp., plus appendices.