The Guiana Shield covers an area of approximately 2.5 million square kilometres with a distinct floristic province consisting of over 8000 species of which approximately 50% are believed to be endemic to the Shield (Maguire, 1970). According to Berry et al (1995), 3763 plant species of 118 genera belonging to 4 families are endemic to Venezuelan Guayana (i.e. Venezuela part of the Guiana Shield of which 61 endemic genera occur in Guyana. Among regional endemic found in Guyana are Victoria amazonica, Arapaima gigas, Pteroneura brasiliensis, and Priodontes giganteus. Chlorocardium rodiei, a prime timber species has a range almost 98% restricted to Guyana. An estimated 20% of GuyanaĆs 500 orchids are endemic to Guyana. Other notable endemic tree species are Dicymbe alstoni, Vouacapoua macropetala, and Swartzia Ieiocalycina, The Guiana Shield is a neotropical centre of endemism (Prance 1982, 1989). Guyana, with an area of 215,000 square kilometers, is one of five countries in the world with a very high percentage forest cover and low human population pressure.
The extremely low population pressure in most of the forest belt has facilitated the occurrence of large expanses of pristine rainforest supporting over 7100 plant species; 1400 chordates; 834 arthropods; 426 fungi; 33 bacteria; 13 nematodes; 44 algae; 17 molluscs and an estimated 30 viruses. The 1400 plus chordates comprise 123 mammals; 711 birds; 102 reptiles; 77 amphibians; and 352 freshwater fish (GAHEF/UNEP 1992). Most of these biodiversity inventory figures have undergone upward revisions recently, with significant increases in the arthropod and fungal taxa. ( Taken from: http://www.unep.org/biosafety/files/GYNBFrep.pdf)
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