Cranwell's horned frog

Cranwell's horned frog (Ceratophrys cranwelli), also called the Chacoan horned frog, is a terrestrial frog endemic to the dry Gran Chaco region of Argentina, Bolivia, Paraguay and Brazil. Like most members of the genus Ceratophrys, they are often considered Pacman frogs because of their resemblance to the popular video game character of the same name. Most adult species range from 8–13 cm (3.1–5.1 in) long and can weigh up to 0.5 kg (1.1 lb).

The backs of these frogs typically have dark green and brown coloration, although albino variants with orange and yellow backs also exist. The dark color scheme aids in camouflaging the animal as it burrows and waits for its prey. Though generally inactive, they are aggressive eaters, and are capable of leaping for several body lengths to capture prey. They use their incredibly sticky tongue to latch onto prey and pull it into their mouth the jaws

Cranwell's are nocturnal and rest with their eyelids open. They are ordinarily carnivorous, feeding mostly on insects and like-sized animals, and are known to cannibalize other frogs. Though they are capable of eating animals almost half their size, Cranwell's sometimes eat things larger than they are. However, due to a row a teeth along their upper jaw, they are unable to release prey from their mouth causing them to potentially die by choking.[1]

At extreme temperatures, Cranwell's frogs enter a period of estivation, developing a thick layer of protective skin to trap moisture and aid in respiration. When estivation is complete, the frog uses its front and hind legs to help shed the protective layer. In many cases, the frog uses its jaws to help pull the skin over its back, often eating the skin in the process.