Alavaro Mesquita was a native Amazonian, who claimed to have a saurian encounter on the shore a swamp in the Rio Purús/Rio Juruá area of the Amazon basin. Whilst fishing along the shore he encountered he saw two red eyes high above the ground. Getting closer he saw what he described as a bipedal reptile, most closely resembling a Camptosaurus
He shot at the animal which fled deep into the swamp. He recounted his tale to a skeptical Rolf Blomberg, who was collecting interviews for his 1966 book Rio Amazonas
Another story, a creationist favourite, comes to us from a 1883 letter to the Scientific American called "A Bolivian Saurian,"
"“Sir,—The ‘Anglo-Brazilian Times,’ March 24th, 1883, says that the Brazilian Minister at La Paz, Bolivia, has remitted to the Minister of Foreign Affairs in Rio photographs of drawings of an extraordinary Saurian killed on the Beni after receiving thirty-six balls. By order of the President of Bolivia the dried body, which had been preserved at Asuncion, was sent to La Paz. It is 12 metres long from snout to point of the tail, which latter is flattened. Besides the anterior head, it has, 4 metres behind, two small but completely formed heads rising from the back. All three have much resemblance to the head of a dog. The legs are short, and end in formidable claws. The legs, belly, and lower part of the throat appear defended by a kind of scale armour, and all the back is protected by a still thicker and double cuirass, starting from behind the ears of the anterior head, and continuing to the tail. The neck is long, and the belly large and almost dragging on the ground. Professor Gilveti, who examined the beast, thinks it is not a monster, but a member of a rare or almost lost species, as the Indians in some parts of Bolivia use small earthen vases of identical shape, and probably copied from Nature.”"
A possible overweight Bolivian sauropod (with multiple heads)?
Wikipedia page and more info here. His son, Brian, later sketched the scene he imagined when he father saw the footprints of this large creature. Note the tail mark dragging in the ground, an artists imagination running away with him as current scientific opinion (and common sense) suggests dinosaurs, especially sauropods, didn't drag their tails!
Another, more detailed, 1907 encounter by Franz Herrmann Schmidt can found here. Reports of this nature by explorers in the Brazil/Peru area in the first half of the 20th century are relatively common. Later in the century we get lots of more recounting of native stories of large Mokele-Mbembe like monsters.
If you think the tales of dinosaurs in the jungles of South America are off-the-wall, just check out some stories from with the United States of America!
In a letter published in the August 22, 1982, issue of Empire Magazine, a Sunday supplement, Myrtle Snow of Pagosa Springs, Colorado, wrote that in May 1935, when she was three years old, she saw "five baby dinosaurs" near her hometown. A few months later a local farmer shot one after it took some of his sheep. "My grandfather took us to see it the next morning," she said. "It was about seven feet tall, was gray, had a head like a snake, short front legs with claws that resembled chicken feet, large stout back legs and a long tail."So as always no evidence (surprisingly the Bolivian Saurian's corpse has never been located!), but plenty of explorers tales!
But these were not her only sightings. There were two more: (1) "1 saw another one in a cave in 1937, but it was dark green." And (2) "On October 23, 1978, as I was returning from Chama New Mexico, about 7:30 P.m., in a driving rain, I saw another one going through the field towards the place where I had seen the one in 1937."
In 1934 a South Dakota farmer claimed that a giant, four-legged reptile forced his tractor off the road before disappearing into nearby Campbell Lake. Investigators found huge tracks on the shore. Prior to this sighting sheep and other small animals had been disappearing mysteriously. Source
Picture of Camptosaurus used under license from FunkMonk
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