Longspurred Mint

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Longspurred Mint

Dicerandra cornutissima

Status	Endangered
Listed	November 1, 1985
Family	Lamiaceae (Mint)
Description	Aromatic shrub with linear, untoothed leaves and purplish-rose flowers.
Habitat	Sand pine scrub.
Threats	Residential development, collection.
Range	Florida

Description

Longspurred mint, Dicerandra cornutissima, is a strongly aromatic shrub, growing to 1.6 ft (0.5 m) tall, with erect, non-woody flowering shoots arising from a woody base. The untoothed, opposite leaves are about 0.6 in (1.5 cm) long, and are covered with conspicuous sunken glands. Flowers, which bloom in September and October, are borne in the upper leaf axils. The corolla is 0.3 in (7 mm) long, tubular and lipped. Flower color is purplish-rose with deep purple markings and a whitish throat. The plant gives off a pleasant, minty aroma.

Although Longspurred mint was long confused with scrub mint, the two are readily distinguishable. Longspurred mint has narrower leaves and purple-rose flowers; its style is smooth or only slightly hairy.

Habitat

Longspurred mint grows in sunny open areas in bare sand pine scrub or oak scrub communities often surrounded by pine-turkey oak sandhill vegetation.

Distribution

The species was first collected in 1938 from Sumter County, Florida; it was later located in adjacent Marion County. The Sumter County plants have since been lost.

Longspurred mint is now found in a single area near Ocala in Marion County. Of two existing populations, one occurs in tracts of scrub in the Ocala Waterway residential subdivision, which is largely abandoned. Several thousand plants were noted at this site in the mid-1980s. Nearby, Marion Oaks, a developing residential subdivision, harbors 1,000 plants. Several hundred plants have been surveyed along Interstate Highway 75 and State Road 484.

Threats

The historic collection sites in Sumter County no longer provide suitable habitat for the plant. In Marion County, some habitat has been developed for housing, and continued development could eliminate the species altogether. Because Longspurred mint is highly visible and strongly aromatic, it can be easily identified by the general public. It grows adjacent to highways and human habitation, and is vulnerable to collectors or vandals.

Conservation and Recovery

Recovery efforts focus on nursery propagation as a way to restore the Longspurred mint to its native habitat along the Sumter Upland. A South Carolina nursery has recently propagated limited numbers of Longspurred mint. Plants are now being cultivated at the Florida Botanical Garden and the National Herb Garden in Washington, D.C.

The Recovery Plan calls for establishing 20 distinct, self-sustaining populations on secure sites. The accomplish this goal, the U. S. Fish and Wildlife Service recommends protecting and managing existing populations; conserving germ plasm for plant propagation; determining ecological and reproductive requirements; and obtaining new suitable habitat sites.