Etonia Rosemary

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Etonia Rosemary

Conradina etonia

StatusEndangered
ListedJuly 12, 1993
FamilyLamiaceae (Mint)
DescriptionMinty rosemary shrub with dense hairs matted under the surfaces of the leaves with sharply bent corolla tube.
HabitatScrub vegetation with sand pine and shrubby evergreen oaks.
ThreatsResidential development, commercial trade, limited distribution.
RangeFlorida

Description

The Etonia rosemary is a shrub that grows up to 5 ft (1.5 m) and has numerous, frequently arching primary branches. The leaves have margins that are tightly rolled to the underside. The dull green upper side of the leaf is covered with short, downy hairs and numerous minute glands. The lower side is slightly paler and concave with tiny hairs that are very dense even on the midrib. The midrib, at the base of a strong median groove on the upper surface, is strongly raised on the lower surface and has two to four strong branch nerves on each side, a characteristic unique to this species of Conradina.

Clusters of three to seven flowers are produced from all or most nodes from the midstem up. The flower's characteristic corolla tube is sharply bent above the middle. The sepals form two lips. The upper lip is three-toothed and upswept while the lower lip with two teeth is split almost to the base. The corolla is strongly two-lipped with a lavender-blue to lavender-rose corolla tube and throat. The upper lip is uniformly lavender and the lower lip and throat have a broad longitudinal zone of white or cream mottled with spots and streaks of deep purple. The four stamens consist of a shorter pair extending almost to the tip of the upper lip and a longer pair extending slightly beyond, arching outward and downward. The pollen sacs on the anthers are dark purple with white hairs. The S-shaped style extends beyond the anthers. Generally, four brown, egg-shaped nutlets are produced. Flowering occurs from early spring to late fall.

Habitat

The Etonia rosemary is found in deep white-sand scrub dominated by sand pine and shrubby oaks, including Chapman oak (Quercus chapmanii ), scrub live oak (Q. geminata ), myrtle oak (Q. myrtifolia ), and some turkey oak (Q. laevis ). Plants of this genus are generally most abundant in natural openings or artificial clearings rather than in the scrub. These mints respond positively to disturbance, which, historically, was probably fire.

Distribution

All known plants are in a platted subdivision near Florahome in Putnam County, Florida.

Threats

This species was not discovered until 1990 and its only known locations are on private lands. All known plants are in a platted subdivision with most plants along unpaved, sandy roadsides. This population would be drastically reduced by any attempt to widen or improve the roads. C. etonia is apparently restricted to very limited areas of deep white-sand scrub with shrubby oaks and sand pines on dry soils. Habitat loss and fire suppression resulting in closure of overstory vegetation are important limiting factors.

Conservation and Recovery

The area where C. etonia was initially discovered is included in a Conservation and Recreation Lands (CARL) project area, Etoniah Creek. This project is part of an acquisition plan to secure a wildlife habitat corridor connecting the Ocala National Forest and Camp Blanding. Upon acquisition, the Etoniah Creek project will be managed by the Division of Forestry as a State Forest. Long range protection of the original site can be achieved when the land is purchased by the State of Florida and management of the scrub habitat is initiated. Little is known about the biology and habitat requirements of the Etonia rosemary because of its recent discovery. This plant requires light and responds to disturbance so its management will involve restoring and maintaining an appropriate stage of scrub habitat succession through prescribed burning or mechanical disturbance.

Contacts

Regional Office of Endangered Species
U. S. Fish and Wildlife Service
1875 Century Blvd., Suite 200
Atlanta, Georgia 30345
http://southeast.fws.gov/

Herbarium
Vanderbilt University
Post Office Box 1705
Station B
Nashville, Tennessee 37235
Telephone: (615 )322-2961

References

Kral, R., and R. B. McCartney. 1991. "A New Species of Conradina (Lamiaceae) from Northeastern Peninsular Florida." Sida 14391-398.

U.S. Fish and Wildlife Service. 1994. Recovery Plan for Etonia Rosemary (Conradina etonia ). U.S. Fish and Wildlife Service, Atlanta, Georgia. 11 pp.