Tetramolopium Lepidotum Ssp. Lepidotum

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Tetramolopium lepidotum ssp. lepidotum

No Common Name

StatusEndangered
ListedOctober 29, 1991
FamilyCompositae (Asteraceae)
DescriptionShrub with lanceolate leaves and flower heads with white ray florets and pale salmon disk florets.
HabitatGrassy ridgetops, slopes, and west-facing cliffs.
ThreatsAlien plant species, low numbers.
RangeHawaii

Description

Tetramolopium lepidotum ssp. lepidotum is an erect shrub of the aster family that grows from 4.7-14 in (12-35.5 cm) in height and branches toward the ends of the stems. The lanceolate leaves are 1.0-1.8 in (2.5-4.6 cm) long. The flower heads are in clusters of from six to 12. Each head contains 21-40 white to pinkish lavender ray florets that are female and four to 11 pale salmon disk florets that are bisexual. This is a short-lived perennial that has been observed producing fruit and flowers from April through July.

This subspecies has been known by several scientific names: Erigeron lepidotus, E. pauciflorus, E. tennerrimus var. lepidotus, T. chamissonis var. luxurians, T. lepidotum var. luxurians, and Vittadinia chamissonis.

The other subspecies, T. lepidotum ssp. arbusculum, is known from a single 1844 collection and is now considered extinct.

Habitat

T. lepidotum ssp. lepidotum occurs only on grassy slopes, ridgetops, and west-facing cliffs at elevations between 1,200 and 3,100 ft (365.7-944.8 m).

Distribution

T. lepidotum ssp. lepidotum was first described in 1934. This species was known on Oahu from nearly the entire range of the Waianae Mountains, from Makua Valley to Kaaikukae Ridge, and from the island of Lanai. The three currently surviving populations on Oahu extend over an area of about 2.5 mi (4 km); in 1997, they numbered between 44-65 total plants. Two or three plants occurred at Kuma Kakii, two at Waianae Kai, and 40-60 at Puu Kaua.

Threats

The main threat to T. lepidotum ssp. lepidotum is competition from several invasive alien plant species. Christmas berry forms dense thickets and may also release chemicals that inhibit the growth of other species. Firetree was planted in the Waianae Mountains during a reforestation project; besides forming a dense closed canopy that excludes other species, it produces its own nitrogen, enabling it to colonize areas to which native species have become adapted. Molasses grass grows in dense mats that smother native vegetation.

Fire is a threat to T. lepidotum ssp. lepidotum populations that lie near the U.S. Army's Makua Military Reservation and Schofield Barracks. Within a 14-month period from 1989 to 1990, ten fires resulted from weapons practice on the reservation.

Conservation and Recovery

The Nature Conservancy of Hawaii has out-planted three individuals in a fenced exclosure within Honouliuli Preserve. These individuals have since died, yet two healthy T. lepidotum ssp. lepidotum have sprouted near the enclosure. One of these was flowering in May 1997, and its vigor was rated as moderate. This species is also being propagated at the National Tropical Botanical Garden.

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/

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

References

Cuddihy, L.W., and C.P. Stone. 1990. Alteration of Native Hawaiian Vegetation: Effects of Humans, Their Activities and Introductions. Cooperative National Park Resources Study Unit, University of Hawaii Press, Honolulu.

Culliney, J.L. 1988. Islands in a Far Sea: Nature and Man in Hawaii. Sierra Club Books, San Francisco.