Researchers scoured the region between 2010 and 2013 and found 258 species of plants, 84 fish (including a vegetarian piranha), 22 reptiles, 18 birds and one new mammal, a monkey that purrs like a cat when it's happy. Many of the species are believed to be endemic to the rain forest and found nowhere else.
Take a look at photographs of a small sampling of the discoveries below, or click here for a full list.
Photos and captions courtesy of the WWF.
Cercosaura hypnoides – Colombia | This beautiful lizard was found from the hatchlings of eggs collected by scientists in the Colombian Amazon. An elusive species, Cercosaura hypnoides, has not been seen in the wild since the original eggs were collected, raising the prospect that it could potentially be endangered.
Sobralia imavieirae – Brazil | Among the new plant species are a large number of new orchid species, including this splendid pink species, Sobralia imavieirae, officially described by scientists from Roraima in the Brazilian Amazon.
Tometes camunani – Brazil | This new species of piranha, Tometes camunani, can span 20 inches wide and weigh up to 9 pounds, and is strictly herbivorous. The freshwater fish inhabits rocky rapids associated with seedlings of plants that grow among the rocks, its main source of food.
Allobates amissibilis - Guyana | This amphibian is already believed to be highly endangered. In fact, its Latin name, Allobates amissibilis, meaning “that may be lost,” alludes to this as the area where it thrives could soon be opened to tourism.
Apistogramma cinilabra - Peru
Callicebus caquetensis – Colombia | This new species, Callicebus caquetensis, is one of about 20 species of titi monkey, which all live in the Amazon basin. The babies have an endearing trait, “When they feel very content they purr towards each other,” explained scientist Thomas Defler.
Chironius challenger – Guyana and Venezuela | Found in the mountains of Guyana, at elevation of 4,922 ft., this brightly-colored snake species was named Chironius challenger after Arthur C. Doyle's fictional character Professor George Edward Challenger in the novel, The Lost World.
Dicrossus warzeli – Brazil | The species is named after Frank Martin Warzel, a skilled German aquarist who first imported the species from the Rio Tapajos to Germany, as well as observed its behaviour, including reproduction in the field in Brazil and Colombia.
Gonatodes timidus - Guyana | This extraordinary-looking species of lizard was discovered in 2011 in the part of the Amazon that extends into Guyana. The surface of the Lizard’s head is black with bluish white to vivid yellow irregular stripes and blotches. Despite this ‘warpaint’ the name given to the species derives from the Latin word timidus meaning “shy” or “fearful”.
Passiflora longifilamentosa –Brazil | A new species of passion flower was discovered in the rain forests of the Brazilian state of Para in 2013. Together with vivid purple petals, the new species displays fantastic and quirky 'noodles' or 'spaghetti' (corona filaments) that burst out of the flower's centre.