Description
This is one of the world’s most famous orchid species. It is endemic to Madagascar and the genus was named, in part, after the Malay word for orchid, Angurek. Heavy, continuous rainfall with no dry season may be part of the reason why this Madagascan endemic can be found growing not only epiphytically on the driest parts of tree trunks, but also, occasionally, lithophytically on rocks and even semi-terrestrially at from sea level to 700 metres. Angraecum sesquipedale’s flowering period can last from from May to November.
During a three month stay in Madagascar, use of a room was kindly offered to me by The Missouri Botanical Garden’s Madagascar outpost in Antananarivo. This enabled me to create this painting initially from a specimen I was shown growing nearby at Tsimbazaza Botanical Garden, but to discover even a few of its associated lichens etc in the wild, I travelled to Noissy Mangabe, Masouala peninsula where I saw it growing lithophytically on a small rocky outcrop. I painted every associated lichen and other plant which were later identified as Pardotrema cristiferum, Pyrenocarp, Coccocarpiia erythroxyli, Parmeliella sp. and Graphidaceae by the Museum of Natural History in London.The moth, Xanthopan morgani praedicta was painted from the Madagascan collection at the Muséum d’Histoire Naturelle, Paris.
There have been many explanations of who wrote what and when about the pollination of this orchid – almost as many as there have been characters who’ve contributed to our knowledge of it. It was collected by the Frenchman Aubert du Petit Thouars, and by the Englishman Ellis, who in 1859 noted during one of his many travels around Madagascar the connection between epiphytes and hummingbirds but thought it may be a moth which pollinated A. sesquipedale. A Sphinx moth was specifically predicted by Alfred Russell Wallace in 1867 – and that it would undoubtedly be found in Madagascar. Wallace was a cash-strapped, multitalented and bold explorer, humanitarian, writer, map-maker, co- founder of biogeography, anthropologist and learner of Malay, who apparently unlike Darwin, loved and respected the different peoples he met and who evolved his own theory of the Evolution of Species virtually simultaneously and independently of the extremely wealthy Charles Darwin. Later, Darwin surmised a moth pollinator after he’d received specimens of the orchid with its astonishing 30 centimetre spur from Robert Bateman. Wallace, as often, was proved correct.
Though both Wallace and Darwin envisaged a pollinating moth with a proboscis the same length as the orchid’s spur – up to a staggering 35 centimetres long, naturally enough, contemporaries were sceptical. Some may even have mocked and guffawed.That is, until such a moth was found forty years later. It does indeed have a proboscis of the correct length and has been reliably photographed pollinating this orchid species but possibly not exclusively as all the field naturalists I met in Madagascar agreed that they had never seen this moth flying whilst the orchid is in flower…….
Further characters contribute to this tale. H.E.K. Jordan was a German entomologist who formed a useful association with the banker turned passionate zoologist Walther Rothschild. Xanthopan morganii praedicta was the name given by them to this sphinx moth in acknowledgement of Wallace’s prediction. Sesquipedale is Latin for one and a half feet, but who or what was Morgan ?
Oblivious to all that, A. sesquipedale emits a spicy scent at night which presumably is attractive enough to X. morgani praedicta and any other pollinators to run the gauntlet of lurking jumping spiders in order to carry on their vital business of helping ensure Angraecums’ survival in the wild. My own conclusions about an almost systematic destruction of Madagascar’s ecology, with it’s 90 % of species found nowhere else on earth, is that, despite heroic efforts by Malagasy and international conservation groups, a combination of extreme poverty, the prevailing mindset reliant on two unsustainable farming practices – slash and burn { tavy } brought to Madagascar by Bornean settlers and the cattle grazing practices brought by Bantu tribesmen combined with sometimes extreme and usually localised rules of behaviour known as Fad or Fady have both destroyed and sometimes protected natural systems and wildlife as each isolated village follows often distinct dictates. For example, one village considers it fady to eat lemurs, so there is a sufficiently large remaining population to delight tourists who had wondered where all the famed wildlife has gone.
I heard of an American pilot who tried to challenge some of the fiercely clung-to, ancestor-sanctioned traditional sayings such as “ The eastern rainforests never end ” by taking local chieftains up in his light aircraft to give them a bird’s eye view of the destruction of the eastern rainforests just beyond their village. I have no idea if it made any difference.© Frances Livingstone 2018
