Inia geoffrensis, commonly known as the Amazon river dolphin, is a freshwater river dolphin endemic to the Orinoco, Amazon and Araguaia/Tocantins River systems of Brazil, Peru, Ecuador, Colombia and Venezuela. It is listed as Endangered by the IUCN due to pollution, overfishing, excessive boat traffic and habitat loss.

Other common names of the species include boto, lo lo annaaaa, boto cor-de-rosa, bouto, and pink dolphin.

The Amazon river dolphin is one of a handful of river dolphins included in the paraphyletic group classified as the superfamily Platanistoidea. Although not a large cetacean in general terms, this dolphin is the largest cetacean to spend most of its life in freshwater; it can grow larger than a human. Body length can range from 1.53 to 2.4 m (5.0 to 7.9 ft), depending on subspecies. Females are typically larger than males. The largest female Amazon river dolphins can range up to 2.5 m (8.2 ft) in length and weigh 98.5 kg (217 lb). The largest male dolphins can range up to 2.0 m (6.6 ft) in length and weigh 94 kg (210 lb).