Vernonia Proctorii

views updated

Vernonia proctorii

No Common Name

ListedApril 27, 1993
FamilyCompositae (Asteraceae)
DescriptionErect, small-sized shrub with knobby stems and trunk; olive-green to grayishgreen leaves, and bright purple flowers.
HabitatSemi-arid mountains of near-vertical slopes in areas of scrub woodland at elevations ranging 886-984 ft (270-300 m).
ThreatsHabitat loss due to agricultural, rural and tourist development.
RangePuerto Rico


Vernonia proctorii is a small erect shrub which may reach a height of 5 ft (1.5 m). The stems and trunk are densely pubescent with silvery uniseriate hairs and with a knobby appearance due to the persistent petiole bases. Leaves are alternate, ovate to orbicular, subsessile or with the petioles appressed to the stem, and from 0.6-1.4 in (1.5-3.5 cm) long and 0.4-2.6 in (1.0-2.6 cm) wide. The upper blade surface is green to olive-green and moderately strigose with scattered glistening globular trichomes. The lower surface is grayish-green, sometimes becoming rusty with age, and densely sericeous. The leaf margins are densely ciliate with silvery hairs. Flowers are borne in terminal clusters of two to five heads, each approximately 0.1 in (3 mm) in length, and bright purple in color. Achenes are from 0.07-0.1 in (2-3 mm) long and sericeous with silvery hairs. During recent studies the species has been observed in flower and fruit during the months of April and May (1994).


V. proctorii is endemic to Puerto Rico and known only from the summit area of Cerro Mariquita in the range of hills known as the Sierra Bermeja, municipality of Cabo Rojo. The population has been estimated at about 950 individuals in an area of several acres.


The site is located within the subtropical dry forest life zone. Average annual precipitation just to the west of the Sierra Bermeja at the Cabo Rojo National Wildlife Refuge is 35 in (88.3 cm) (1980 through 1993). The drier period extends from December through March, and the wetter period includes May and September through November.


In the Sierra Bermeja the population occurs on privately owned land which is currently subject to intense pressure for residential and tourist development. The Sierra Bermeja has also been included in a copper and gold mining proposal currently under consideration. Clearing of land for grazing has destroyed some habitat which may have been occupied by this species. In addition, fire in this dry southwestern range of hills is common, particularly during the drier months. Currently the species is only known from one locality; therefore, the risk of extinction is extremely high.

Conservation and Recovery

This species is currently being threatened by intense agricultural, rural and tourist development. The land on which this species occurs is being cleared for grazing by cattle and goats. Adjacent land is being subdivided for sale in small farms, and tourist/urban developments.


U. S. Fish and Wildlife Service
Boqueron Ecological Services Field Office
P.O. Box 491
Boqueron, PR 00622-04
Telephone: (809) 851-7297
Fax: (809) 851-7440

U. S. Fish and Wildlife Service
Regional Office, Division of Endangered Species
1875 Century Blvd., Suite 200
Atlanta, Georgia 30345


U.S. Fish and Wildlife Service. 27 April 1993. "Endangered and Threatened Wildlife and Plants; Determination of Endangered Status for Three Puerto Rican Plants." Federal Register. 58(79): 75755-25758.