No Common Name
|Listed||February 25, 1994|
|Description||Small shrub with alternately arranged, single-veined, sparsely hairy or hairless linear leaves, and bell-shaped reddish purple flowers.|
|Habitat||Mossy banks at the base of cliff faces within the spray zone of waterfalls or along streams in lowland wet forests.|
|Threats||Competition from alien plants, natural disaster, limited numbers.|
Lysimachia filifolia is a small shrub in the primrose family that reaches 0.5-1.6 ft (15.2-48.8 cm) in height. The linear leaves measure 0.6-2.1 in (1.5-5.3 cm) long, 0.01-0.07 in (0.3-1.7 mm) wide, and are usually alternately arranged. They are single-veined and sparsely hairy or hairless. The bell-shaped flowers are reddish purple, 0.2-0.4 in (5.1-10.2 mm) long, and borne singly on flower stalks about 0.7-1.2 in (1.8-3.0 cm) long that elongate upon fruiting. Fruits are thick, hard capsules about 0.2 in (5.1 mm) long that contain numerous minute, nearly black, irregularly shaped seeds. This species is distinguished from other members of the genus by the shape and width of its leaf, and by calyx lobe shape and corolla length.
L. filifolia typically grows on mossy banks at the base of cliff faces within the spray zone of waterfalls or along streams in lowland wet forests at an elevation of 800-2,200 ft (244-671 m). Associated plants include mosses, ferns, liverworts, pili grass, Cuphea carthagenensis, and Pilea peploides.
L. filifolia was known historically only from the upper portion of Olokele Valley on Kauai. The species is now also known from the headwaters of the Wailua River at Wialeale on Kauai and the slopes of Waiahole Valley in the Koolau Mountains of Oahu. These populations are located on state land.
The populations on Kauai are located within a 0.5-sq mi (1.3-sq km) area and total 76 individuals, of which 20-75 occur in the Waialeale population. The Oahu population contains about 150-200 individuals.
The major threat to L. filifolia is competition with alien plants. Individuals of this species on Kauai are damaged and destroyed by natural rock slides in their habitat, which is near the bottom of a steep cliff. Marsh pennywort, tarweed, and thimbleberry, although not invasive weeds, are present in this near pristine area of Wailua Stream and may degrade the native ecosystem. At least one feral pig has made its way into this area, indicating that this disruptive animal is a potential threat.
Individuals on Oahu are vulnerable to rock slides and compete for space with alien plants, such as marsh pennywort, tarweed, Hamakua pamakani, and octopus tree.
Because only one population occurs on each of only two islands, the species is threatened by stochastic extinction. Hurricane Iniki caused at least some damage to the Wailua River population.
Conservation and Recovery
L. filifolia has been successfully propagated and then cultivated by Lyon Arboretum and National Tropical Botanic Garden. The Lyon Arboretum held five plants in the greenhouse in 1995, and National Tropical Botanic Garden held seeds in storage in 2000.
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
Senior Resident Agent Office
U.S. Fish and Wildlife Service
300 Ala Moana Boulevard, Room 7-235
P.O. Box 50223
Honolulu, Hawaii 96850-5000
Telephone: (808) 541-2681
Fax: (808) 541-3062
U.S. Fish and Wildlife Service. 25 February 1994. "Endangered and Threatened Wildlife and Plant; Determination of Endangered or Threatened Status for 24 Plants from the Island of Kauai, HI." Federal Register 59 (38): 9304-9329.