Schiedea helleri

No Common Name

Descripton

Schiedea helleri, a vine of the pink family, has mostly prostrate stems that are smooth below, minutely hairy above, at least 0.5 ft (15 cm) long, and possess internodes at least 1.6 to 6 in (4-15 cm) long. The opposite leaves are somewhat thick and range from 4 to 5.5 in (10-13.7 cm) long and 1.8 to 2.4 in (4.5 to 6 cm) wide. The leaves are triangular, egg-shaped to heart-shaped, conspicuously three-veined, and nearly hairless to sparsely covered with short fine hairs, especially along the margins. The perfect flowers occur in loose and open branched clusters, each branch being 8 to 10.2 in (20 to 15.5 cm) long. The flower contains three styles and probably ten stamens. The fruits are capsules, about 0.12 to 0.13 in (3 to 3.2 mm) long. This species differs from others of the genus that grow on Kauai by its viney habit.

A plant specimen was collected in 1895 on Kauai that was named S. helleri in 1943 in honor of its collector. Listed as possibly extinct in the current treatment of the family, S. helleri was later collected on Kauai by botanists from National Tropical Botanical Garden.

Habitat

S. helleri occurs on steep cliffs in closed, 'ohi'auluhe, montane, wet tropical forest.

Distribution

For almost 100 years, S. helleri was known only from Kaholuamano above Waimea on Kauai; in 1993, this species was discovered on a steep wall above a side stream off Mohihi Stream, approximately 3.5 mi (5.6 km) north of the original location. The only known population consists of 30 to 40 mature individuals found on a steep cliff in closed 'ohi'a-uluhe montane wet forest on state-owned land, within or close to the Alakai Wilderness Preserve, at approximately 3,500 ft (1,050 m) elevation. Other native plants growing in association with this population include hapu'u, kanawao, 'olapa, Cyanea hirtella (haha), Dianella sandwicensis ('uki'uki), and Viola wailenalenae. The federally endangered Poa sandvicensis is also found here.

Threats

Competition with the noxious alien plant prickly Florida blackberry and a risk of extinction from naturally occurring events and reduced reproductive vigor due to the small number of extant individuals in the only known population are serious threats to S. helleri. Pigs have not yet been reported from this drainage, but pose a potential threat since they are found in nearby areas off Mohihi Stream.

S. helleri has populations close to trails or roads, making these plants susceptible to overcollection by plant enthusiasts. Prickly Florida blackberry is also a threat.

Conservation and Recovery

The S. helleri is only known from population of 30 to 40 mature plants on a particular cliff on State-owned land, within or close to the Alakai Wilderness Preserve. This critical habitat must be strictly protected from potential invasion by mammalian herbivores, and the abundance of alien invasive plants should be reduced. Seeds and cuttings of the S. helleri were collected by the National Tropical Botanical Garden, but did not germinate or survive. Its populations should be monitored, and research undertaken into its biology and ecological requirements. Additional work should be done to ensure the S. helleri can be propagated in captivity, to supply stock for out-planting to supplement the extremely small wild population.

Contact

U.S. Fish and Wildlife Service
Ecological Services
300 Ala Moana Boulevard, Room 3-122
P.O. Box 5088
Honolulu, Hawaii 96850-5000
Telephone: (808) 541-3441
Fax: (808) 541-3470

Reference

U.S. Fish and Wildlife Service. 10 October 1996. "Endangered and Threatened Wildlife and Plants; Determination of Endangered or Threatened Status for Nineteen Plant Species From the Island of Kauai, Hawaii." Federal Register 61 (198): 53070-53089.