The Cuvier's dwarf caiman is a small harmless crocodile native to South America. It is sometimes kept in captivity as a pet and may be referred to as the Wedge-head caiman by the pet trade. Cuvier's dwarf caimans have strong body armor on both its dorsal (upper) and ventral (lower) sides. Their head has an unusual shape for a crocodilian, with a dome-shaped skull and a short, smooth, concave snout with an upturned tip, the shape rather resembling the head of a dog. The upper jaw extends markedly further forward than the lower jaw. Adults are dark brownish-black with a dark brown head, while juveniles are brown with black bands. The irises of the eyes are chestnut brown at all ages and the pupils are vertical slits.
Cuvier's dwarf caimans are found in northern and central South America. They are present in the drainages of the Orinoco River, the São Francisco River, and the Amazon River, and the upper reaches of the Paraná River and the Paraguay River. The countries in which they are found include Peru, Ecuador, Colombia, Venezuela, Guyana, Surinam, French Guiana, Brazil, Bolivia, Trinidad and Tobago, and Paraguay. Cuvier's dwarf caimans are freshwater reptiles and are found in forested riverine habitats and areas of the flooded forest around lakes. They prefer rivers and streams with fast-flowing water, but they are also found in quiet, nutrient-poor waters in Venezuela and southeastern Brazil. In the northern and southern parts of their range, these caimans are also found in gallery forests in savannah country, but they are absent from such habitats in Los Llanos and the Pantanal.
Cuvier's dwarf caimans are mainly nocturnal. During the day, they sometimes lie up in burrows or rest on piles of rocks or sun themselves while lying, facing the sun, in shallow water with their backs exposed. They may aestivate (similar to hibernation state) in the burrow to stay cool in the dry season. Cuvier's dwarf caimans are home both in water and on land. They are able to travel quite large distances overland at night and sometimes may be found in isolated, temporary pools. Adult caimans are usually found singly or in pairs. They communicate with each other through sounds, movements, postures, smells, and touch. When threatened, caimans inflate their body to seem bigger and may also hiss aggressively.
Cuvier's dwarf caimans are carnivores ( insectivores, piscivores). Adults feed on fish, amphibians, small mammals, birds, crabs, shrimp, mollusks, and other invertebrates, which they catch in the water or on land. Juveniles eat less fish, but also consume crustaceans, tadpoles, frogs, and snails, as well as land invertebrates, such as beetles.
Cuvier's dwarf caimans are polygynous which means that one male mates with multiple females in a single breeding season. The breeding of this species has been little studied, but it does not appear to be seasonal in nature. The female builds a mound nest out of vegetation and mud somewhere in a concealed location and lays a clutch of 10 to 25 eggs, hiding them under further vegetation. The incubation period lasts around 90 days and the gender of the hatchlings depends on the temperature of the nest during that time. When the eggs begin to hatch, the female opens the nest in response to the calls made by the young. Newly emerged babies have a coating of mucus and may delay entering the water for a few days until this has dried. Its continuing presence on their skin is believed to reduce algal growth. The female stays with her young for a few weeks, after which time the hatchlings disperse. The young grow at a rate of around 8 to 10 cm (3 to 4 in) per year and reach reproductive maturity when they are 8 years old.
Cuvier's dwarf caimans are threatened by habitat destruction, including the mining of gold, intensive agriculture, and urbanization. They are also killed by indigenous peoples for food, traditional medicine and are collected for the pet trade.
According to IUCN, the Cuvier's dwarf caiman is locally common and widespread throughout its range but no overall population estimate is available. Currently, this species is classified as Least Concern (LC) on the IUCN Red List and its numbers today are stable.
Cuvier's dwarf caimans are very important for their ecosystem. Due to their diet habits, they maintain a healthy balance of organisms. In their absence, fish, such as piranhas, might dominate the environment. Cuvier's dwarf caimans are also important prey species for local predators. The eggs and newly hatched young are preyed on by birds, snakes, rats, raccoons, and other mammals. Adults are protected by the bony osteoderms under the scales and their main predators are jaguars, green anacondas, and large boa constrictors.