Temporal range: Late Paleocene - Present
| Paleosuchus trigonatus|
|Smooth-fronted caiman distribution (green)|
The smooth-fronted caiman (Paleosuchus trigonatus), also known as Schneider's dwarf caiman or Schneider's smooth-fronted caiman, is a crocodilian from South America, where it is native to the Amazon and Orinoco Basins. It is the second-smallest species of the family Alligatoridae, the smallest being Cuvier's dwarf caiman, also from tropical South America and in the same genus. An adult typically grows to around 1.2 to 1.6 m (3.9 to 5.2 ft) in length and weighs between 9 and 20 kg (20 and 44 lb). Exceptionally large males can reach as much as 2.3 m (7.5 ft) in length and 36 kg (79 lb) in weight.
The head of the smooth-fronted caiman is similar in appearance to that of the spectacled caiman (Caiman crocodilus), but no bony ridge or "spectacle" occurs between the eyes. The scutes on the back of the neck and the tail are large, triangular, and sharp. It has heavily ossified body armour on both its dorsal and ventral surfaces. The relatively short tail is broad at its base and flattened dorsoventrally in contrast to most species of crocodilians which have laterally flattened tails. The bony scutes on the tail have sideways projections; and the tail is so well armoured, that it is relatively inflexible. This caiman is a dark greyish-brown with mid-brown eyes. Males grow to about 1.7 to 2.3 m (5 ft 7 in to 7 ft 7 in) long, with the largest recorded specimen being 2.6 m (8 ft 6 in). Females do not often exceed 1.4 m (4 ft 7 in). It is a robust crocodilian, strong for its size, and tends to carry its head high with its neck angled upwards.
Distribution and habitat
The smooth-fronted caiman is native to the Amazon and Orinoco Basins in South America and is found in Bolivia, Brazil, Colombia, Ecuador, French Guiana, Guyana, Peru, Suriname, and Venezuela. It inhabits small streams in forested areas where in some cases, the water may be insufficiently deep for it to completely submerge itself. It is seldom seen in open areas and does not usually bask in the sun, even in captivity.