A fire-tailed titi monkey and pink river dolphin are among 381 species discovered in the Amazon in a two-year period, a new report shows.
One bird, 20 mammals (including two fossils), 32 amphibians, 93 fish, 19 reptiles and 216 plants were detailed in the report — the third in a series, which covers 2014 and 2015 — by conservation group the World Wildlife Fund (WWF) and Brazil's Mamiraua Institute for Sustainable Development.
The fire-tailed titi-monkey, Plecturocebus miltoni, was among the new species discovered.
It is from the southern Amazon and — as its name suggests — has a long, bright orange tail.
A new species of pink river dolphin Inia Araguaiaensis was also found, and it is estimated there are about 1,000 individuals.
Stingray species Potamotrygon limai, which has a honeycomb pattern on its surface, was found in the Jamari River.
The largest one observed measured about 65 centimetres.
The lizards discovered included Rondonops xanthomystax, which is dark brown, with black streaks on the sides of its head — a yellow moustache.
A new animal or plant species is discovered in the Amazon every two days — "the fastest to be observed this century", the WWF said.
"We're in 2017, verifying the existence of new species and, even though such resources are scarce, we are seeing an immense variety and richness of biodiversity," WWF-Brazil Amazon program coordinator Ricardo Mello said in a statement.
"This is a signal that we still have much to learn about the Amazon."
He said it was a reminder biodiversity "needs to be known and protected".
The WWF said several of the newly-discovered species were under threat, including from deforestation.
"The findings come as huge parts of the forest are increasingly under threat, sparking further concern over the irreversible — and potentially catastrophic — consequences unsustainable policy and decision-making could have," it said.