The Lost World of Venezuela: Some Observations on Carnivorous Plants in the Guyana Highlands

Andreas Wistuba, Joachim Nerz

Germany

In the Southern part of Venezuela there is one of the most remote and bizarre landscapes in the world: the Guyana highland with about 120 flat-topped table-mountains or tepuys (Indian: house of gods). These are spectacular sandstone-mountains with mostly vertical walls and vast plateaus on their tops. Due to the isolation of each mountain, there is a very high degree of endemism. The ground is very poor and sandy, useless for agriculture. Therefore the whole area remains nearly undisturbed until today. Because of the difficulties to travel in this region the whole area remained nearly unexplored until very recently, and now there are still "white spots" on the maps of this area! One of the most prominent early naturalists who visited the lowlands of the Orinoco/Casiquare-river was the German Alexander von Humboldt. A further important early expedition was undertaken by another German naturalist, Schomburgk. He was the first one to travel extensively in the savannahs of the Guyana Highlands. He was able to get to the foot of the famous Mt. Roraima. For the first time he found there a new member of the Sarraceniaceae: Heliamphora nutans. But until that time, nobody had ever been on the top of these mystery mountains. In 1884, the British naturalist Evard F. Im Thurn was able, to climb Mt. Roraima and he was very impressed by the unique plateau. Tate reached the top of Mt. Duida with about 70 helpers in the year 1928. Here he found the second species of Heliamphora, which was named later in honour of him: Heliamphora tatei. Extensive fieldwork was undertaken by botanists of the Botanic Gardens of New York and Missouri in the fifities and sixties of the 20th century. Many new tepuys were visited and explored, mostly by helicopters and many new species were described by Julian Steyermark, Bassett Maguire, John Wurdack and many other botanists.

Due to the poor soil, the area is one of the richest carnivorous plant habitats in the world, with many spectacular members of the genera Heliamphora, Brocchinia, Drosera, Genlisea and Utricularia! In 1988 and 1999, we visited the area and our main interest was to find some of the lesser known Heliamphora species, including Heliamphora ionasii, the most impressive Heliamphora species. Nearly nothing was known about this species before. It was just collected once by the American botanists (Maguire et al.). Beside this, we did some explorations at Roraima-Tepuy and Kukenan-Tepuy and in the lowlands of the Guyana highlands. The intention of the second expedition was to reach Cerro de la Neblina, the most remote of all tepuys, hidden deep in the Amazonian jungle. Due to its remoteness, it was discovered in 1956, just 40 years ago. From this time, all Brazilian geographic books had to be corrected. With its altitude of 3000 m, it is now the highest mountain of Brazil. The aim of this expedition was to find one of the Heliamphora species with long pitchers: Heliamphora tatei neblinae. The results of these expeditions will be presented in this talk.