[The "nivrées", or ichthyotoxic plants of French Guyana].
An attempt to clarify the taxonomy, the biogeography and the ethnobotany of the fishing poisons of Guiana and adjacent countries is presented. Collections have been made for every drug and field-notes concerning all ethnic groups of Guiana. Data are compared with published sources, particularly those of the past centuries. Ichthyotoxic plants have been classified into three groups: rotenone-yielding plants (Lonchocarpus, Derris, Tephrosia), saponin-yielding plants (Sapindaceae), and the "kunami" group of plants (Compositae, Euphorbiaceae). For each drug the vernacular names, the synonyms still used, the most notable morphological characteristics are specified, as well as ethnological observations and active constituents when known. Drugs and fishing-related techniques were selected long ago by Amerindians then often diffused through Amazonian countries by mixed-blood populations.