Assessment of Conservation Status of the Family Orchidaceae: Possibly Extinct Species of Bangladesh

Abstract

^{The status of occurrence of orchid taxa and their probable threats have been assessed throughout Bangladesh especially in the recorded areas of orchid species. The assessment was based on long- term field investigation, collection and identification of orchid taxa; examination and identification of herbarium specimens preserved in different national and international herbaria and survey of relevant up to date floristic literature. Enumeration of these orchid taxa is provided with updated nomenclature and short annotation about habitats, phenology, potential values, recorded locality, global distribution, conservation status and list of specimens available in different herbaria. 32 orchid species belonging to 22 genera, out of 187 total recorded species, are recognized as extinct from the flora of Bangladesh due to anthropogenic and natural causes. These have neither been collected nor reported to occur elsewhere in Bangladesh for more than 50-100 years and could not be located in their recorded localities through field investigations. Among these extinct species, 12 are epiphytic in nature and 20 species are terrestrial and more than 50% are economically very important for their potential medicinal, horticultural and ornamental values. It is apparent that, while orchids are so numerous and widespread, many are threatened with extinction. Orchids of limited geographical range are severely threatened. Many orchids, by the nature of their life-style, are naturally rare and confined to limited areas. Immediate action plans are required to combat the threat of extinction of this valuable plant group.}