Comprehensive Description

The orchid genus Angraecum holds a special place in the history of pollination biology and evolutionary biology. Charles Darwin famously received some specimens of Angraecum sesquipedale from Madagascar, the flower of which has a nectar tube nearly 30 cm long. After careful study, Darwin predicted in his 1862 treatise on the reproductive biology of orchids that only a giant hawkmoth with a "wonderfully long proboscis" would be able to pollinate this spectacular orchid. Forty-one years later, the predicted moth pollinator, Xanthopan morganii var. praedicta, was found in the primary forests of Madagascar (although effective pollination of the orchid by this insect was only demonstrated 135 years after Darwin’s prediction). (Micheneau et al. 2009 and references therein)

Many of the approximately 200 Angraecum orchids show numerous clear adaptations for pollination by large moths, but this is not the case for all members of the genus. Angraecum cadetii represents one such exception. Recent work indicates that this species, found only on the islands of Reunion and Mauritius in the Indian Ocean, is pollinated by a not yet described gryllacridid, or "raspy cricket", a cricket-like orthopteran insect. This represents the first clearly supported case of orthopteran-mediated pollination in a flowering plant. (Micheneau et al. 2010)