ONLINE IMAGE COLLECTION

About the Image

This is a photograph of Ledothamnus sessiliflorus N.E. Brown (Ericaceae: blueberry family). The genus of seven species (Luteyn 1995) is found only in the Guiana Highlands of northern South America, a region known for its pristine habitat and highly endemic flora. Ledothamnus was thought to be endemic to tepui summits of the Venezuelan Guyana. During the summer of 2004, it was collected in Guyana by Dr. David Clarke (Univ. of North Carolina-Asheville), Stephen Stern (Univ. of Utah), Diana Gittens (Univ. of Guyana), Amerindian collaborators, and myself from the summit of Mt. Maringma. Maringma, slightly east of Mt. Roraima, is the highest tepui wholly within Guyana (2200 m / 7200 ft.) and was previously unexplored biologically. Its tepui summit hosts genuine cloud forests characterized by quaking bogs, rocky outcrops, and dense, tangled vegetation. At 5° N latitude, environmental parameters are extreme and include harsh winds and bouts of intense rainfall then intense sunshine. The photo of Ledothamnus sessiliflorus shows its 8-parted flower with a superior, verrucose ovary. Its morphology and growth form are bizarre in appearance, like so many other tepui plants. On Maringma it occurs as a stunted, ankle-high "terrestrial" shrublet. Luteyn used adjectives such as "wiry" and "gnarled" to help describe it in his taxonomic treatment (1995). Such discoveries of endemic and other plants of the Guyanese tepuis point to the need for further botanical research in the area and better conservation strategies of this truly unique and eccentric ecosystem. The L. sessiliflorus specimen has been deposited in the United States National Herbarium, as part of the Smithsonian's Biodiversity of the Guianas Program. Luteyn, J.L. (ed.). 1995. Ericaceae--Part II. The Superior- Ovaried Genera. Flora Neotropica Monographs. Vol. 66.