Na Pali Beach Hedyotis

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Na Pali Beach Hedyotis

Hedyotis st.-johnii

StatusEndangered
ListedSeptember 30, 1991
FamilyRubiaceae (Coffee)
DescriptionSucculent, slightly woody trailing perennial with clusters of green flowers.
HabitatSea cliffs.
ThreatsLow numbers, feral goats.
RangeHawaii

Description

Na Pali beach hedyotis (Hedyotis st.-johnii ) is a succulent perennial herb of the coffee family with slightly woody, trailing, quadrangular stems up to 1 ft (0.3 m) long. The fleshy leaves clustered toward the base of the stem are broadly ovate to broadly elliptic, 2-6 in (5.1-15.2 cm) long, and about 2 in (5.1 cm) wide. Clusters of flowers are borne on 3-6-in-long (7.6-15.2-cm-long) flowering stems. The leafy, broadly ovate calyx lobes are about 0.1 in (2.5 mm) long and wide, enlarging in fruit to about 0.4 in (1 cm) long and wide. The green petals are fused into a tube about 0.2 in (5.1 mm) long and wide.

The fruit consists of kidney-shaped capsules with dark brown to blackish angular seeds. Na Pali beach hedyotis is distinguished from related species by its succulence, basally clustered fleshy leaves, shorter floral tube, and large leafy calyx lobes when in fruit.

Habitat

Na Pali beach hedyotis grows in the crevices of north-facing, near-vertical coastal cliff faces within the spray zone, a coastal area below 250 ft (76.2 m) in elevation. The associated habitat is sparse dry coastal shrubland that supports native species like ahinahina and akoko and invasive alien plants like sourbush.

Distribution

Na Pali beach hedyotis is known only from state-owned land in Na Pali Coast State Park, and the most recent collections of the plant were made from a 4.5-mi long (7.2-km long) section of this coastline at Nualolo Valley, Nualolo Kai, Milolii Beach, and the area between Kalalau and Honopu beaches. Na Pali beach hedyotis is still extant in all of those areas except perhaps Nualolo Kai. Fewer than 200 individuals have been seen in these four populations, with some populations numbering as low as one plant. Another population with two groups of ten total individuals was discovered on Polihale Ridge in 1991. Similar inaccessible habitat might harbor asyet-undiscovered individuals.

Threats

Goat predation and habitat degradation are the major causes for the decline of this species. As a result of past goat activity, Na Pali beach hedyotis is now almost entirely restricted to sites inaccessible to goats. The major current threat is competition from sourbush and other aggressive alien plants. Other potential threats are landslides and fire.

Conservation and Recovery

Na Pali beach hedyotis has been successfully propagated and then cultivated by National Tropical Botanical Garden, where seeds of this species are also in storage.

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/

Pacific Remote Islands Ecological Services Field
Office
300 Ala Moana Blvd., Room 3-122
P.O. Box 50088
Honolulu, Hawaii 96850
Telephone: (808) 541-1201
Fax: (808) 541-1216

Reference

U.S. Fish and Wildlife Service. 1995. "Recovery Plan for the Kauai Plant Cluster." U.S. Fish and Wildlife Service, Portland, 270 pp.