Junín Giant Frog

T. macrostomus is completely aquatic, and restricted to lakes (notably Lake Junín) and waters that are directly connected to them like rivers, streams and canals. It has also been introduced to the upper part of the Mantaro River, but it is unclear if this population persists. It is found both in large marshy lakes and smaller deep lakes. This smooth-skinned, dark brownish frog generally ranges from shallow water to a depth of 12 m (39 ft), but prefers places with extensive aquatic vegetation and 1–5 m (3–16 ft) deep. In its native habitat the water temperature typically is between 7 and 17 °C (45–63 °F). Captives have been kept in aquariums for more than 5 years at around 20 °C (68 °F). It feeds on aquatic snails (especially Physidae), amphipods, aquatic insects (especially Baetidae mayfly larvae) and small fish. T. macrostomus is among the largest frogs in the world and the largest exclusively aquatic frog, a title sometimes incorrectly awarded to its somewhat smaller relative, the Titicaca water frog (T. culeus). T. macrostomus measures up to 30 cm (12 in) in snout–vent length, and 70 cm (28 in) in total length including outstretched legs. It can weigh up to about 2 kg (4.5 lb), and the hindlegs alone can surpass 40 cm (16 in) in length. Very large individuals are rare; most adults have a snout–vent length of 12.4–17.3 cm (4.9–6.8 in) and weigh less than 0.5 kg (1.1 lb). …