|Listed||August 26, 1988|
|Description||Evergreen shrub, typically branching from the base, with lanceolate leaves.|
|Habitat||Evergreen forests on volcanic slopes.|
|Threats||Deforestation, commercial development, purposeful eradication.|
Erubia, Solanum drymophilum, is an evergreen shrub that occasionally reaches the size of a small tree, 18 ft (5.5 m). Usually, a number of stems branch from the woody base. Sharply spined, lance-olate leaves with untoothed margins are arranged alternately on the branches. White, fan-shaped flowers are gathered into spikes (racemes) at the ends of the stems. Branches, leaves, and flowers are all covered with fine, white hairs. The fruit is a round black berry.
This shrub grows in evergreen forests on volcanic slopes that range from 1,000-3,000 ft (300-900 m) in elevation. It is associated with an area of rocky out-crops known as Las Tetas de Cayey. Seventy percent of the plant's historical habitat has been converted to pastureland; 10% is planted in coffee; 3% farmlands; and 7% ungrazed forest where erubia survives. Although there is much surface water from precipitation, perennial streams, and lakes, there is little ground water. The temperature is moderate with little variation between summer and winter.
Endemic to the lower montane region of southeastern Puerto Rico, erubia was probably locally common at one time. Many historic populations have been lost to deforestation and to purposeful eradication by farmers, who viewed the plant as a threat to livestock because of its sharp spines. When listed in 1988, erubia was known from a single population of 200 plants.
The privately owned site of about 5 acres (2 hectares) that hosts the only known population of erubia is threatened by commercial and residential development that has already claimed adjacent tracts.
Conservation and Recovery
Erubia produces large quantities of viable seed, and with proper care seedlings grow rapidly. If surviving plants can be protected from cutting, the population should be able to replenish itself in a short time. The U. S. Fish and Wildlife Service (FWS) has been actively involved in acquiring the site and/or providing for conservation and management of the habitat. Pending the results of ongoing research into the plant's biology, it is probable that FWS specialists will recommend transplanting erubia to other sites within the historic range that can more easily be protected. Collected seeds will be used to establish a nursery stock to provide plants and cuttings for reestablishment.
Regional Office of Endangered Species
U.S. Fish and Wildlife Service
1875 Century Blvd., Suite 200
Atlanta, Georgia 30345
Boquerón Ecological Services Field Office
P.O. Box 491
Boquerón, Puerto Rico 00622-0491
Telephone: (787) 851-7297
Fax: (787) 851-7440
Silander, Susan. 1988. "Determination of Endangered Status for Solanum drymophilum." Federal Register 53(166):43701.
Vivaldi, J. L., and R. O. Woodbury. 1981. "Status Report on Solanum drymophilum Schulz." Report. U.S. Fish and Wildlife Service, Atlanta.