Morgan’s Sphinx (Xanthopan morgani). It is known for being the pollinating insect of the orchid Angraecum sesquipedale, commonly known as Darwin’s Orchid. In 1862, Charles Darwin wrote in the margin of his observations on the flower of Angraecum sesquipedale: “This species, whose large, star-like flowers of white wax have excited the admiration of travellers in Madagascar, cannot fail to be noticed. Below the labellum hangs a green nectary of extraordinary length, resembling a whip. (…) It may be asked what purpose a nectary of so disproportionate a length can serve. I think we shall soon be persuaded that the fertilization of the plant depends on such a length and on the presence of nectar only in the lower portion. We are astonished that any insect should be capable of reaching this nectar. (…) but in Madagascar there must exist moths whose proboscises can be extended to ten or eleven inches!’ Darwin’s hypothesis, which was initially received with disdain by entomologists, was confirmed in 1873 following the discovery in Brazil of some species of sphingids with proboscises of compatible dimensions. In 1871 Alfred Russel Wallace went so far as to propose that the pollinating insect of A. sesquipedale could be precisely Xanthopan morgani, but only in 1903 did the entomologists Lionel Walter Rothschild (1868-1937) and Karl Jordan (1861-1959) identify with certainty the sphingid lepidopteran as a pollinator of the orchid, describing it as Xanthopan morganii praedicta, where the epithet praedicta constituted an acknowledgement of Darwin’s “prediction”.
