Jones Cycladenia

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Jones Cycladenia

Cycladenia humilis var. jonesii

StatusThreatened
ListedMay 5, 1986
FamilyApocynaceae (Dogbane)
DescriptionPerennial herb with bright green leaves and rosy flowers.
HabitatSemi-arid scrub.
ThreatsOff-road vehicles.
RangeArizona, Utah

Description

Jones cycladenia, Cycladenia humilis var. jonesii, is an herbaceous perennial. Dark green leaves, broadly ovate and cupped, occur in pairs, clustered toward the base. The plants put up a single, erect flowerstalk, up to 6 in (15 cm) tall, bearing many pink or rose-colored, trumpet-shaped flowers, resembling small morning glories. It grows in colonies of stems and new runners are sent out from a deep rhizome.

Habitat

Jones cycladenia survives in badland habitats in semi-arid central Utah, usually on the steep slopes of hills or mesas. It grows in fine textured soils derived from sandstone at elevations of 4,500-5,600 ft (1,400-1,700 m). Surrounding vegetation is sparse, desert scrub. This plant community typically occurs along the lower edge of higher elevation pinyon pine and juniper forests. Associated plants are Mormon tea, shrubby wild-buckwheat, and a perennial sunray (Enceliopsis nudicaulis ). A sub-species of this last plant found in Nevada, the Ash Meadows sunray (E. n. corrugata ), is federally listed as endangered.

The Canyonlands section of Utah has more endemic plantsabout 70than any other part of the state. More than a dozen other Canyonlands species are candidates for listing under the Endangered Species Act.

Distribution

Jones cycladenia is the only member of its genus occurring in the intermountain West. Because it is found in three isolated areas more than 100 mi (160.9 km) apart and the nearest related species are in California, Jones cycladenia is believed to be a relict (survival) species from the Tertiary period.

The species was collected and described in 1882 from Pipe Spring (Mohave County), Arizona, but that population, if it still exists, has not been relocated.

Jones cycladenia is currently found in three Utah countiesEmery, Garfield, and Grand. After being considered extinct for a number of years, the plant was rediscovered in 1979 in the San Rafael Desert (east of the San Rafael Swell and south of Interstate 70 in Emery County). One site, with some 2,000 plants, was situated on public land managed by the Bureau of Land Management (BLM); a second site supported about 500 plants on state land.

In 1984 a population was located in the Purple Hills within the Circle Cliffs area of the Glen Canyon National Recreation Area (Garfield County), about 90 mi (144.8 km) south of the San Rafael Swell population. In 1985, about 1,000 plants were located in Castle Valley (Emery County) on BLM land, and another 1,000 plants were found to the northeast along Onion Creek below Fisher Mesa. A recent U. S. Fish and Wildlife Service (FWS) survey discovered a large population of perhaps 5,000 plants in Grand County.

As of 1987 the total number of known stems was more than 10,500. Since many of the mature stems are clones of the same plant connected by underground rhizomes, the actual number of plants is hard to determine.

Threats

The arid climate and harsh soils constitute a fragile ecosystem, which is easily degraded and slow to recover from disturbance. Oil and gas leases have been issued near all known population sites, and there has been active exploratory drilling adjacent to the Castle Valley site. Off-road vehicles at Castle Valley and Fisher Mesa have destroyed numerous plants. Sites in the Purple Hills lie within the uranium-bearing Chinle formation, and the area is open to mining claims. Annual exploration and assessment work, required to maintain a valid claim, causes continual disturbance of the habitat.

Conservation and Recovery

Because of this species' threatened status, a review is now required for activities on federal land that might affect populations. Although mineral leases and exploration permits are typically considered on a case-by-case basis, the FWS is working with the BLM to redesign land use policies in the region. If left alone, the plant has a good chance of stabilizing its population and surviving.

Contacts

Regional Office of Endangered Species
U.S. Fish and Wildlife Service
P. O. Box 1306
Albuquerque, New Mexico 87103
http://southwest.fws.gov/

Regional Office of Endangered Species
U.S. Fish and Wildlife Service
P.O. Box 25486
Denver Federal Center
Denver, Colorado 80225
http://www.r6.fws.gov/

References

Holmgren, N. H. 1984. "Cycladenia." In A. Cronquist et al, eds., Intermountain Flora, Vol. 4. New York Botanical Garden, Bronx.

U.S. Fish and Wildlife Service. 1986. "Rule to Determine Cycladenia humilis var. jonesii (Jones cycladenia) to be a Threatened Species. " Federal Register 53: 16526-16530.

Welsh, S. L. 1970. "New and Unusual Plants from Utah." Great Basin Naturalist 30:16-32.

Welsh, S. L. 1984. "Flora of the Glen Canyon National Recreation Area." Report. Glen Canyon National Recreation Area Research Management Team, Page, Arizona.

Welsh, S. L., N. D. Atwood, and J. L. Reveal. 1975."Endangered, Threatened, Extinct, Endemic, and Rare or Restricted Utah Vascular Plants." Great Basin Naturalist 35:327-376.

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Jones Cycladenia

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