More than 1,200 new species have been discovered in the Amazon in the past decade. Each discovery - including this 4m-long Anaconda boliviana, described in 2002 - is outlined in a new WWF report.
The report, Amazon Alive, summarises discoveries between 1999 and 2009. The new species include 637 plants, 257 fish, 216 amphibians, 55 reptiles, 16 birds and 39 mammals, including this marmoset Mico acariensis.
The report does not include new insect species, which WWF says are almost too numerous to count. This Ranitomeya benedicta frog lives in lowland plains between the Huallaga and Ucayali rivers in central Peru.
Many species are threatened by habitat destruction, while for some their beauty is their downfall. Many of these dwarf chiclids (Apistogramma baenschi), native to the Rio Huallaga in Peru, are collected and exported.
This recently discovered tiger-striped tarantula, Cyriocosmus nogueiranetoi, inhabits the Brazilian state of Acre, an area that the organisation says is home to a particularly rich variety of species.
The Amazon River dolphin or pink river dolphin was described in the 1830s. In 2006, scientists reported a separate species of the dolphin in Bolivia (Inia boliviensis). Some researchers consider this a subspecies.
The bald-headed parrot, Pyrilia aurantiocephala, is known in just a few localities in the Lower Madeira and Upper Tapajos rivers in Brazil - a region under threat from logging.
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