In honor of Brett's greatest achievement....I have prepared a speech...
In the past 125 years all five of the world's rhinoceros species--the Indian, Javan, and Sumatran rhinos in Asia, and the black and white rhinos in Africa--nearly went extinct. And some of the African rhinos were quite literally taking a large fly with them on their slide toward extinction. Most people, even in scientific circles, had no idea the fly existed. They still don't. Certainly no one considered conservation programs for the fly while the rhinoceros populations were plummeting. Such a lack of concern about threats posed to insects and other invertebrates is not uncommon, but it is irresponsible. At least 95 percent of all animal species inhabiting the Earth are invertebrates, and so they constitute the bulk of animal diversity on the planet. Luckily for the endangered rhinoceros fly, conservationists were inadvertently drawn to its cause.
The plight of the big, charismatic rhinoceroses caught the world's attention in the 1990s; their populations had fallen drastically because of poaching, the illegal trade in their horns, and the destruction of their natural habitats. Today in Asia, only about 2,500 Indian, 300 Sumatran, and sixty Javan rhinos remain. Both African species, though, have benefited greatly from sustained and well-publicized conservation efforts. The white rhinoceros, the world's second-largest land mammal, has two subspecies, one of which lives in southern Africa and now numbers more than 11,000. After declining to as few as twenty individuals at the end of the nineteenth century, the southern white rhino has become one of Africa's biggest conservation success stories. (The other white rhino, a central African subspecies, numbered more than 2,000 in the 1960s, but only five or ten individuals are left, making it critically endangered.) Populations of the black rhinoceros fell by a staggering 96 percent between 1970 and 1992; the species is still endangered, but the population has risen to 3,500.
Rebounding from near extinction along with the black and white rhinos is a large fly, commonly known as the rhinoceros bot fly (Gyrostigma rhinocerontis), which parasitizes them. The fly has the distinction--because of its robust appearance and body weight--of being the largest fly species known in Africa.
Like other bot flies, the immature form of the insect is a spiny maggot, or hot, that burrows into its host and feeds off the host's tissues--in this case the gut of the black or the white rhino. After three stages, or instars, of growth, the maggot worms its way out through its host's anus and metamorphoses into a short-lived fly that can start the cycle over again by laying eggs on the hide of its host. Because G. rhinocerontis depends entirely on its hosts for survival, its numbers would have mirrored the rise and fall of rhinoceros populations in all parts of Africa. In some periods of the twentieth century, it must have been close to extinction.
About 24,000 known species of flies, in slightly more than a hundred different families, live in the Afrotropics, a region that includes sub-Saharan Africa, Madagascar, and associated islands in the Atlantic and Indian oceans. Beyond those species, a substantial number still await scientific description and classification. Estimates differ, but I would venture that at least 30,000 more African fly species remain unknown to science.
Even within that astonishing context, few entomologists would dispute the exceptional nature--both visually and biologically--of G. rhinocerontis, in the family Oestridae. The largest adult specimens grow as long as 1.6 inches, with wingspans as wide as 2.8 inches, making it one of Africa's most striking fly species.
The rhinoceros bot fly was originally discovered in the stomach of an African rhinoceros more than 160 years ago. The adult form of the species strongly resembles a large, blackish wasp, with an orange and reddish head and long, slender legs that are notably paler than the rest of the body. The elongated wings are brown to black and, when the fly is at rest, run along almost the entire length of the body. Adult flies occur in parts of Africa where their rhinoceros hosts live. In recent years that has meant the grasslands and savannas of southern and East Africa, but historically the flies and their hosts extended, except for the Congo Basin, across most of sub-Saharan Africa. No matter the flies' range, even the most experienced collectors have had a tough time finding them.
Two other bot-fly species of the genus Gyrostigma are known, and both are exceptionally rare. One of them, G. conjungens, was discovered in its bot form in the belly of a Kenyan black rhinoceros in 1901, but it hasn't been collected, or even seen again, since 1961. The other rare species, G. sumatrensis, is known only from a single bot, which was in the late developmental stage of the larva known as the third instar. It was discovered in a captive Sumatran rhinoceros and described in 1884, but it, too, has not been seen again. No Gyrostigma bot flies have been found in the Indian or the Javan rhinos, but it is not unreasonable to expect that the intestinal parasites may eventually be discovered in all five rhinoceros species.
Later, QD.
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Originally Posted by Boostless
