Catesbaea melanocarpa

No Common Name

Description

Catesbaea melanocarpa, of the family Rubiaceae, belongs to a genus that consists of 10 or more species of spiny shrubs. Most are confined to the Antilles, but some may extend into the Bahamas and the Florida Keys. In Puerto Rico, two species are known— C. melanocarpa and C. parviflora. These two species are differentiated by the size and color of the fruits; black and larger, 0.19-0.23 in (4.8-5.8 mm) in diameter in the former, and white and smaller, 0.07-0.15 in (1.7-3.8 mm) in diameter in the latter.

Catesbaea melanocarpa is a branching shrub that may reach approximately 10 ft (3 m) in height. Spines occur on the stems between the leaves. Leaves are small, from 0.19 to 1 in (4.8-25.4 mm) long and 0.07 to 0.58 in (1.7-14.7 mm) wide, often in clusters, and the small stipules (appendages at the base of the leaf stalk) are deciduous (shed seasonally). The flowers are white, solitary or paired, and almost sessile (attached directly at the base) in the axils. The corolla (petals) is funnelform and from 0.31-0.39 in (7.8-9.9 mm) long. The fruit is globe-shaped, 0.19 to 0.23 in (4.8-5.8 mm) in diameter, and black with a brittle fruit wall. The two-celled fruit contains five to seven seeds in each cell.

Habitat

The Catesbaea melanocarpa occurs in subtropical dry forest.

Distribution

Catesbaea melanocarpa is known historically from Puerto Rico, St. Croix in the U. S. Virgin Islands, Barbuda, Antigua, and Guadeloupe. In Puerto Rico, it is currently known from only one location in Cabo Rojo; in the U. S. Virgin Islands, it is known from one location near Christiansted, St. Croix. Both populations are located on privately owned land subject to intense pressure for development for residential, tourist, and industrial purposes.

Threats

This plant is located on privately owned land. In Cabo Rojo, a residential/tourist development has been proposed, consisting of a hotel, condo-hotel, residential villas and lots, a golf course, and other associated facilities. In St. Croix, only one population, consisting of about 24 plants, is known to exist. This population is located on privately owned land near Christiansted and is subject to pressure for development.

One of the most important factors affecting the continued survival of this species is its limited distribution. Because so few individuals are known to occur in limited areas, the risk of extinction is extremely high. Catastrophic natural events, such as Hurricane Hugo in 1989, may dramatically affect forest species composition and structure, felling large trees and creating numerous canopy gaps.

Conservation and Recovery

The only known populations of Catesbaea melanocarpa are located on privately owned land. Since there is no federal ownership, and the species is not currently in trade, the only potential threat would relate to removing or damaging the plant in knowing violation of commonwealth or territorial law. The U. S. Virgin Islands' regulation states that no person may harass, injure or kill, or attempt to do the same, or sell or offer for sale any specimen, or parts or produce of such specimen, of an endangered or threatened species. Unless development is permitted on this land, the landowners do not appear to threaten the species.

Potential introduction sites within unoccupied lands are available on lands under federal management (Cabo Rojo, Laguna Cartagena, and Sandy Point National Wildlife Refuges) and commonwealth management (Guánica Commonwealth Forest). As managers of these subtropical dry forest-lands, the U. S. Fish and Wildlife Service and the Puerto Rico Department of Natural and Environmental Resources are actively involved in conservation activities. Both agencies are committed to the protection of these forested areas.

Contacts

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

U. S. Fish and Wildlife Service
Boquerón Field Office
P.O. Box 491
Boquerón, Puerto Rico 00622-0491
Telephone: (787) 851-7297
Fax: (787) 851-7440

References

Breckon, G., and D. Kolterman. 1993. " Catesbaea melanocarpa Krug & Urban [Rubiaceae]." Final Report under Cooperative Agreement No. 14-16-0004-92-970 between the U. S. Fish and Wildlife Service and the University of Puerto Rico, Mayaguez Campus.

Center for Plant Conservation. 1992. "Report on the Rare Plants of Puerto Rico." Missouri Botanical Garden, St. Louis, Missouri.

Howard, R. A. 1989. Flora of the Lesser Antilles. Leeward and Windward Islands. Volume 6 . Dicotyledoneae— Part 3 . Arnold Arboretum, Harvard University, Jamaica Plain, Massachusetts, 658 pp.

Liogier, H. L., and L. F. Martorell. 1982. Flora of Puerto Rico and Adjacent Islands: A Systematic Synopsis. Editorial de la Universidad de Puerto Rico, Rio Piedras, Puerto Rico, 342 pp.

Proctor, G. R. 1991. Puerto Rican Plant Species of Special Concern. Status and Recommendations. Publicacion Cientifica Miscelanea No. 2. Departamento de Recursos Naturales de Puerto Rico. San Juan, Puerto Rico, 197 pp.

Puerto Rico Planning Board. 1995. "Draft Environmental Impact Statement for Monte Carlo Resort and Boquerón Bay Site." San Juan, Puerto Rico, 88 pp.

U. S. Fish and Wildlife Service. 17 March 1999. "Determination of Endangered Status for Catesbaea melanocarpa." Federal Register 64(51): 13116-13120.