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Situated on the north-eastern shoulder of South America, Guyana lies over the biologically rich Guyana Shield region. Guyana has a land mass of 215,000 square km (83,000 sq. mi.) divided by the major river systems of the Essequibo, Demerara, and Berbice which flow into the Atlantic Ocean. Its many ecosystems can be divided into three main types: the coastal plain, the savanna, and the rainforest.
The coastal plain is a low-lying, flat, fertile strip ranging from 15 to 65 km (9 - 40 mi.) wide. It extends 432 km (268 mi.) from the Orinoco River in the west to the Corentyne River in the east. Although it is only 4% of the total land area in Guyana, it is the principle food producing region with major agricultural crops of rice and sugar. Because of the ease of access, the agriculture, and the cooling sea breeze, most Guyanese (estimated 800,000) live along the coast. Because of the agricultural activities and population, little of the coastal vegetation remains intact.
The savannas of Guyana are of two major types. The Rupununi savanna, which is shared with Brazil and Venezuela, is the largest. This typical dry savanna in the south-west is the major cattle producing area in Guyana. In the northeast region there are tropical wet and semi-wet savannas centering on the Berbice River system.
Rainforest covers the rest of Guyana, approximately 170,000 square km (65,600 sq. mi.) or 80% of the land mass. The rainforest is actually make up many different types of forest, including greenheart, dry evergreen, seasonal, montane, and lowland evergreen as well as swamp forest. Relatively pristine, this area has a rich biodiversity with natural habitats that have high levels of endemism. This region is also rich in Guyana's natural resources, such as, bauxite, diamonds, gold, kaolin, and manganese. The timber and mining industries, in response to Guyana's need for economic development, have placed accelerated pressures on the native vegetation.
Brief Geological History
The Guiana Shield is a unique biogeographic region on the Atlantic seaboard of South America. Its land mass, 1,800,000 square km (695,000 sq. mi.), is defined by the Orinoco River, the Amazon River and Atlantic Ocean. It overlaps several political areas. Most of the Shield is covered by the Venezuelan Highlands, Guyana, Surinam, and French Guiana, but it also includes smalls part of Columbia and northern Brazil. Geologically, the base layer of the Guiana Shield is of Precambrian origin (4 billion - 590 million years ago) with portions covered by the Cretaceous Roraima sandstone (140 - 68 million years ago).
The Roraima formation is believed to have been laid down in the Cretaceous period as shallow marine or brackish water deposits. It consists of pink, yellow and white sandstones, red quartzite, green, black and red shales, conglomerates and boulder beds. Substantially eroded, the formation generally ranges from 500 - 1200 m (1,641 - 3,937 ft.) in elevation. The area is best known for its table top mountains (tepui) made famous by the book "The Lost World" by Arthur Conan Doyle (1912). Nearly all of the table top mountains of the Roraima formation are found in Venezuela or Guyana. The highest part of the formation lies on the Venezuela/Brazil border with Neblina (3085 m; 10,122 ft.) as the largest and highest tipui. The Roraima formation continues east into Guyana forming the Pakaraima Mountains which contain such peaks as Mt. Roraima (2730 m; 8960 ft.), Mt. Ayanganna (2020 m; 6630 ft.), and Mt. Wokomung (2000 m; 6562 ft.). The rivers of the Pakaraima Mountains flow north and east into several rivers most of which empty into the Essequibo and into the Atlantic Ocean. While the vegetation of the Venezuelan part of the Roraima formation is the subject of a series of books (Flora of the Venezuelan Guayana, Steyermark et al., 1995-1997), the plants of the Pakaraima Mountains in Guyana are not as well known.
The Pakaraima Mountains are the source of many rivers which are renowned for their waterfalls that drop off the edge of the escarpment. Perhaps the most famous waterfall is Kaieteur Falls where the Roraima formation gives way to the lowlands. Here the water from the Potaro River drops 226 m (741 ft.) to the splash basin below before leaving the escarpment behind. Kaieteur is second in height only to Angel Falls, Venezuela (918 m; 3012 ft) and five time the height of Niagra Falls, New York, and unlike Angel Falls, Kaieteur carries a large volume of water year round.
Kaieteur, located along the Potaro River at 5º10' N latitude and 59º29' W longitude, is the site of the only national park in Guyana. Established in 1929 by the British Commonwealth, Kaieteur National Park originally encompassed 114 square km (44 sq. mi.). In the early 70's the park boundaries were reduced to 19.4 square km (7.5 sq. mi.) around the falls to take advantage of the mineral resources of the area (Lechner, 1997). In 1993 the Government of Guyana passed legislation to expand the park to 580 square km (224 sq. mi.) and is in the process of drafting a comprehensive plan to manage the area as a potential for ecotourism and national pride. It is hoped that these efforts will conserve the inherent natural beauty Kaieteur for future generations.
In addition to outstanding geophysical features, the Potaro Plateau supports many different habitats. In some areas the forest opens onto a wide shrub-herb "guiana type" savanna. Absent of all but a few trees, the pink sands support scattered shrubs and a dense mat of small herbaceous plants that appear in the wet seasons. During the rainy season, on the almost bare, flat sandstone a "rupicolous vegetation" appears. Numerous species of lichens and delicate herbs such as the tiny terrestrial bladderworts (Utricularia), the small blue flowered herb, Burmannia bicolor, and the sundew (Drosera kaieteurensis) spring up out of tiny cracks and on the surface of the rock. The large bromeliad, Brocchinia micrantha, takes advantage of humus caught in larger cracks and crevice and can grow up to 3-3.5 meters in height. The water that collects in the base of B. micrantha leaves (also referred to as the tank) provides a home for an assortment of animals and plants. One such plant is the largest of the bladderwort, Utricularia humboldtii. The bladders on its aquatic root system capture insects that accumulate in the stagnant waters and digests it for its nutrients. The inflorescence of U. humboldtii, with its light purple flowers, can reach the height of six feet above the bromeliad tank. A smaller species of bromeliad, Brocchinia reducta, which grows on the grass savanna and trees, was first collected and described from Kaieteur Falls. This species was thought to be endemic to the area until it was later collected in Venezuela (Soderstrom, 1963). Another interesting bromeliad from the this region is the cabbage-head bromeliad, Aechmea brassicoides, so named from the habit of the inner leaves folding into a cabbage-like head. It can be found in and on the trees that make up the small "bush islands" over the savanna. The bright yellow flowers of the "yellow-eyed grass" (Xyridaceae) are seen everywhere as well as the small white flowered herbs of the family, Eriocaulaceae.
Along the river the white sand forests are composed of numerous tree species, such as wallaba (Eperua), species of the Brazilnut (Lecythidaceae) and the coffee (Rubiaceae) family. The understory of these forests supports Heliconia, Marantaceae, and many species of Melastomataceae.
As the mist rises from the gorge, a cloud forest habitat is created at the top of the falls along the riparian forest which supports more epiphytes than a typical rain forest, yielding tree branches covered with mosses, orchids, ferns and aroids. In the gorge near the splash basin, the vegetation is bathed in a continuous fine mist. The cool ambient air creates a unique habitat that scientists are just beginning to understand. The steep cliff face and the slippery rocks make collecting difficult. The small ferns, Grammitis mollissima grow on moss laden rocks and tree trunks, bromeliads line the steep walls of the gorge and a primitive species of bromeliad, Navia sandwithii is found in the moist shaded area of boulders. In additions, two species of the african violet family in the genus, Rhoogeton, are only found growing in the splash basin habitat where they are constantly bathed by the mist of water. This red-flowered african violet has been reported near Mt. Roraima in a similar habitat (Toogood, 1983).
There are several endemic species of plants found in the Kaieteur area including a member of the family Rapateaceae, endemic to the Guiana shield, and recently described fern, Hecistopteris kaieteurensis.
The Kaieteur area has been explored by a number of botanical collectors including historical collectors such as, G.S. Jenman (1879), D.B. Fanshawe (1944), B. Maguire & R. Cowan (1955), and R. Cowan & T. Soderstrom (1962). Recent collectors from the Smithsonian's Biological Diversity of the Guiana Shield (BDG) Program and the University of Guyana (UG) include L. Gillespie (BDG), D. Gopaul (UG), T. Henkel (BDG), C.L. Kelloff (BDG), L.P. Kvist (BDG), H. Lall Persaud (UG), J.J. Pipoly (BDG), and S. Tiwari (UG).
Little is know about the animal species of the Potaro Plateau. Preliminary studies from recent visits by specialists include G. Bourne (UMSL), S. Lehman (US), R. Reynolds (USGS), M. Tamessar (UG), and D. Wilson (US) have indicated that this area is particularly rich in animal life, and that the presence of previously unidentified species is probable. Historically, agouti, paca, tapir, red brocket deer, collared peccary, bushmaster, labaria, jaguarundi, raccoon, golden frogs, and tegu have been recorded for this area. Although the fauna inventories for the area are incomplete, there are a number of animal considered under CITES to be extremely rare (in a broad geographic range). Important species known to be in the area are the cock-of -the-rock bird, as well as bush dogs (Speothos venaticus, CITES-extremely rare). A pair of hyacinth macaws (CITES-extremely rare) has been seen flying over Kaieteur and may be nesting somewhere in the area.
Along with the many plant species found in Kaieteur National Park, a visitor may hear the low "hollow" voices of howler monkeys in the distance, can watch the circling of the white throated swifts directly over the falls, or see a pair of scarlet macaw flying overhead. On the trail to Johnson's View one can find the cock-of-the-rock with it bright orange feathers sitting on a low branch to peer inquisitively at you. And none will ever forget the early morning call of large pheasant-like bird, chacalaka, locally called "the bush alarm clock".
This publication is part of a series of checklists designed to provide information on the flora and fauna of Guyana's most interesting areas. The botanical list published here contains approximately 1100 species in 129 families, about 17% of the total number of species that have been recorded for Guyana, Surinam, and French Guiana. This is no doubt an underestimation of the total taxa of the area since tree and epiphyte families are poorly represented in this list. However, we publish this checklist as a preliminary effort to work toward a more complete list of the plants of the area.
Future publications planned for Kaieteur National Park are checklists of herpafauna, mammals, and birds. Still to be organized are lists of the various insect groups about which we know little or nothing.
How To Use This ChecklistThis Checklist of the Plants of Kaieteur National Park has been compiled using literature and plant data of recent and historical collections from the U.S. National Herbarium, New York Botanical Garden, British Museum, Royal Botanic Gardens - Kew, and University of Utrecht. For those that wish to use keys, selected families in the "Flora of the Guianas" publication series (Görts-van Rijn, 1989-1997) and the "Flora of Suriname" (Pulle et al., 1932-1984) are a good source. A brief description has been written for each family using those characters found within the floral area. The scientific names of the plants are alphabetized under each family. Some vernacular names have been add at the family level, where possible, and notes on endemics and cultivars have been included, where known, at the species level.
A few line drawings have been added to represent each family. They are arranged alphabetically by family. In the checklist, an asterisk placed after a species name indicates that there is an illustration for that species. All illustrations have been borrowed from published books and floras and are cited at the end of the section.
The area of South America covered by the Guiana Shield is not only diverse in political boundaries, culture, and language but also of its ecosystem. The eroded Roraima formation has produced the table top mountains of Venezuela and extends to the Pakaraima Mts. of Guyana. As scientists explore the various habitats, they are finding not only new species but also that many plants and animals are endemic to this region. The vegetation of the Venezuelan part of the Roraima formation is a subject of a series of books, Flora of the Venezuelan Guayana (Steyermark et al. 1995-1998) and although work is currently going on to document the flora of the Guianas (Flora of the Guianas, Görts-van Rijn, 1989-1997), the Pakaraima Mountains in Guyana are the least known. It is hoped that the Checklist of the Plants of Kaieteur National Park will help to enlighten the student and plant enthusiast about the unique plants that inhabit this area, and develop an awareness for the inherent natural values of this unique community.
We thank the Smithsonian Institution's Biological Diversity of the Guiana Shield Program for its financial support during this project; John Boggan and Tom Hollowell for providing an update of new entries as identifications were received from the specialists; Susan Grose, Marilyn Hansel, Ashish Rastogi, and Tim Yerington for their assistance in searching for illustrations in the library; and M.T. Strong and Dr. R.A. DeFilipps for proofreading the manuscript. In Guyana, we thank those from the University of Guyana, D. Gopaul, Dr. I. Ramdass, P. daSilva, and M. Tamessar; from the Guyana Park Commission, David Kaultky and Carl Rogers; from the Ministry of Health, Dr. Gail Teixera; and a special thanks to Margaret and Malcolm Chan-A-Sue who have assisted our research team with flight logistics and have provided excellent photographic opportunities over the falls and well as a wealth of knowledge on the flora and fauna. And finally, we thank the many taxonomists who graciously review their specialist family. This is number 28 in the Smithsonian's Biological Diversity of the Guiana Shield Program publication series.
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Doyle, A.C. 1912. The Lost World. The Penguin Group. London, England.
Ek, R.C. 1990. Index of Guyana Plant Collectors. In: A.R.A. Görts-van Rijn (ed.), Flora of the Guianas. Koenigstein, Germany.
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Fairbridge, Rhodes W. 1975. The Encyclopedia of World Regional Geology, Part 1. Dowden, Hutchingson & Ross, Inc. Stroudsburg, Pennsylvania.
Fanshawe, D.B. 1952. The vegetation of British Guiana: A preliminary review. Imperial Forestry Institute paper no. 29: 1-96.
Gansser, A. 1954. The Guiana Shield (South America). Ecolog. Geol. Helv. 47:77- 117.
Gibbs, A.K., C.W. Montgomery, P.A. O'day & E.A. Erslev. 1986. The Archean- proterozoic transition: evidence from the geochemistry of metasedimentary rocks of Guyana and Montana. Geochimica et Cosmoschimica Acta 50:2125-2141.
----------. 1988. Crustal evolution revisited: Reply to comments by S.M. McLennan and S.R. Taylor, and J. Veizer, on "The Archean-Proterozoic transistion: Evidence from the geochemistry of metasedimentary rocks of Guyana and Montana". Geochimica et Cosmochimica Acta 52: 793-795.
Görts-van Rijn, A.R.A. [editor]. 1989-1997.Flora of the Guianas. Koeltz Scientific Books, Germany.
Im Thurn, E. 1934. Thoughts, Talks, and Tramps. Oxford Univ. Press. London, England.
Lechner, L. 1997. Infrastructure Development at Kaieteur National Park. Prepared for the World Bank and the Government of Guyana: National Protected Areas System Guyana Project.
Leechman, A. 1913. The British Guiana Handbook. The Argosy Co., Ltd. Georgetown, British Guiana.
Lindeman, J.C. & S.A. Mori. 1989. The Guianas. In: D.G. Campbell & H.D. Hammond (eds.), Floristic Inventory of Tropical Countries. The New York Botanical Garden. Bronx, New York.
MacKnight, J. 1991. World Wildlife Fund, Draft Strategic Plan for Guiana: 1991-1995. Report produced by WWF-US.
Maguire, B. and collaborators. 1948. Plant exploration in Guiana in 1944, chiefly to the Tafelberg and the Kaieteur Plateau - 1. Bull. Torrey Bot. Club. 75(1): 56 - 115.
Maguire, B. 1970. On the flora of the Guayana Highland. Biotropica 2(2):85-100.
McLennan, S.M. & S.R. Taylor. l988. Crustal evolution: comments on "The Archean- Proterozoic transition: evidence from the geochemistry of metasedimentary rocks of Guyana and Montana" by Gibbs, A.K., C.W. Montgomery, P.A. O'day & E.A. Erslev.
Montgomery, P.A. O'day & E.A. Erslev. Geochimica et Cosmoschimica Acta. 52: 785- 787.
Mori, S.A. & G.T. Prance. 1987. Chapter VI. Phytogeography. In: S.A. Mori & collaborators, The Lecythidaceae of the Lowland Neotropical forest: La Fum‚e Mountain, French Guiana. Mem. New York Bot. Gard. 44:55-71.
Pulle, A., J. Lanjouw, A.L. Stoffers, & J.C. Lindeman. 1932-1984. Flora of Surinam. vol. 1-4. J.H. de Bussy, Ltd. Amsterdam.
Soderstrom, T.R. 1963. Collecting bromeliads in British Guiana. Brom. Soc. Bull. 13(3): 54-60.
Steyermark, J.A., P.E. Berry, & B.K. Holst [editors]. 1995-1998. Flora of the Venezuelan Guayana, vol. 2-4. Missouri Botanical Garden. St. Louis, Missouri.
Toogood, A. 1983. Plant trek to the lost world. The Garden (RHS) 108(4):133-136.
World Wildlife Fund. 1991. Kaieteur National Park, Guyana: Diagnostic Report. World Wildlife Fund. Washington, D.C.
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