The Minhocão (name means "big earthworm" in Portuguese) is a giant subterranean worm-like cryptid reported to dwell underground in the South American forests. These creatures are described as enormous limbless beings with scaly black skin, a readily visible mouth and a couple of tentacle-like appendages protruding from the head. According to at least one witness, it also has a pig-like snout. Although this species is principally fossorial, it also has aquatic habits. It has been reported to prey on large surface animals, including cattle, by suddenly capturing them from below the water.
The minhocão is most well known for the enormous tunnels it leaves behind, which suggests a body diameter of up to ten feet. Its body length is stated to vary, from 75 up to 150 feet. There have been cases of houses and other man-made structures collapsing, and rivers having their course altered, allegedly due to the minhocão's burrowing activity. These tunnels most commonly appear after periods of continuous rain, indicating that the minhocão is more active during such periods, and might even keep itself hidden during dry days. The beast's tunnels will sometimes flood, creating subterranean water bodies.
If the minhocão is real, several theories have been raised about its possible nature. In spite of the name, and the fact that oversized earthworms have proved to be real in many places, including South America, Africa and Australia; it seems unlikely that the minhocão is in fact an earthworm due to its tough skin and carnivorous habits. A more likely identity, proposed by cryptozoologist Karl Shuker, is that the minhocão is in fact a new species of giant caecilian. Caecilians are a poorly known group of amphibians with worm-like, limbless bodies, subterranean-aquatic habits and tentacle-like sense organs on the head. Also, most caecilians do inhabit the forests of South America. Thus, the minhocão fits the description perfectly, except for its size. Other, less accepted ideas include a monstrous-sized lungfish, slug, or snake.
Bernard Heuvelmans, author of the famous cryptozoology book On the Track of Unknown Animals suggested that the minhocão may actually be a surviving glyptodont species. However, unlike their modern relatives, the armadillos, there is no evidence that glyptodonts had burrowing habits. Whatever kind of creature the minhocão was, if real, it appears to be extinct now, as there have been no reported minhocão sightings in the past 130 years.