There are some creatures that live on the edge of reality, from Bigfoot to the Loch Ness monster. Brazil has it's share too.
The Mono Grande, Didi or Maricoxi
The Wild Man of the Woods. There have been reports of "ape men" in the Amazon region since the days of the conquistadors, Pedro de Cieza de Leon reporting Indian legends of them in 1533, and Francis Drake recorded similar rumours. "Sightings" have surfaced every now and again since. There was even a photo published in the Illustrated London News in 1929, and a scientific name suggested (Ameranthropoides loysi).
Reports have been remarkably consistent from 1769 onwards. The Mono Grande are apes about 5 ft tall, more or less upright and covered in short dark hair. If angry they throw sticks, or their own faeces in one report (which might be more effective). It has to be said that these reports have not been universally accepted, or at all in a serious sense. The fact that these forests are home to both Indians who are about 5ft tall, and spider monkeys who are 3ft tall but covered in short black hair, has not gone unremarked.
As an aside, one of the most popular comedians in Brazil goes by the name "Didi".
The Mapinguari, Mapinguary or Isnashi
Once upon a time Brazil was home to giant ground sloths. It really was, their fossils have been found. They were very successful and spread throughout the Americas, some weighing up to 5 tons and with a reach of up to 17ft if standing on their hind legs.
It is suggested that some of these are the mapinguari (or mapinguary or Isnashi ) a large, noisy, smelly and red haired animal supposedly found in the rainforests of Brazil & Bolivia, the "fetid beast". The mapinguani has powerful arms and long claws, and can stand on its rear legs when threatened, which is very giant sloth like. After all, radio carbon dating shows they were still around in at least 2,700 BC (on Cuba), not so long ago, or maybe the mapinguari could be a folk memory passed down from that time. One intriguing connection is that the mapinguari is supposedly bullet (or at least arrow) proof and giant sloths had hides toughened against predators with small bony plates.
Ok, these actually exist. The term "anaconda" refers to a group of similar snakes, but is usually used for the Common Ananconda (Eunectes murinus) which can be up to 22ft long, which is pretty impressive,
It's really hard to actually get a good measurement for various reasons. Firstly, anacondas are aquatic and so are difficult to see, or recover if killed. And to be measured they pretty much have to be killed, as 22ft of muscle is really hard to capture and hold in a straight line. Secondly, specimens don't preserve well, and skins can stretch up to 50% in the drying process.
But the ones we are talking about are bigger - much bigger. The renowned Britsh explorer, Percy Fawcett, reported in 1907 killing one measuring 62 ft long, and he had been told by a Brazilian Boundary Commission official of one in the River Paraguai of over 80ft. Through the 1920s, 30s and 40s there were various claims to have seen snakes of 60-70ft long though no hard evidence.
Two little asides. Several witnesses report that, in addition to it's great length, the snake had glowing eyes, visible when the snake was underwater. Fawcett also comments on the awful stench, which local Indians claimed had a stupefying effect.
Basically "Big Earthworm" in Portuguese, and that's what it looks like, a gigantic earthworm about 1 metre thick and up to 25 m long, with small horns. It is capable of taking cattle and of ruining orchards with its burrows. During the late 19th century there were reports from as far apart as Parana, Goias and Uruguay, mostly in waterlogged ground by rivers, but little since.
Now, there are creatures called caecilians, basically carnivorous legless amphibians which burrow in damp ground, and they can be up 5ft long. A large one of these and a very active imagination could maybe produce the Minhocao.
Legendary beasts of the Guarani
The Guarani are a tribe from the interior of Brazil, to the south and west. Their pantheon of gods includes some interesting examples of, er, speculative biology, such as ...
The Mboi Tui
The "snake-parrot" is just that, a huge snake with the feathered head of a parrot. He lives in marshes like the Pantanal and lets out a terribly loud squawk if disturbed. Actually, the Mboi Tui is just one of lots of "feathered serpents" found in American legends, Aztec and Mayan temples are full of them. If you want to look at it one way, this is suggestive of a shared folk memory - or cultural drift, take your pick.
The Ao Ao
The Killer Sheep. A huge animal resembling a sheep or peccary. Unfortunately it also has a large pair of fangs and is completely carnivorous. The Ao Ao eats only man, chasing its prey with a howling "Ao Ao Ao". It is implacable, chasing its chosen prey relentlessly until caught - climb a tree and it will dig to undermine the roots until you fall. Should you be faced with an Ao Ao the only way to escape is apparently to climb a Palm tree, as it dislikes these and will go looking for other prey.
More details on the cryptozoology can be found at.... The CryptoWeb web site http://www.fortunecity.com/roswell/siren/552/regional.html