Xenopus – Clawed frog

This genus encompasses a unique group of aquatic amphibians native primarily to sub-Saharan Africa. These frogs are highly distinctive in appearance and biology and behavior, making them a subject of interest in scientific research and as exotic pets.

One of the most striking features of Xenopus frogs is their lack of tongues and visible ears, combined with their powerful, webbed hind feet adapted for a life spent entirely in water. The “clawed” part of their name comes from the three black claws on each of their hind feet, which they use to tear apart their food. This is unusual as most frogs use their tongues to catch prey. Xenopus frogs have smooth, slippery skin, usually mottled in shades of green and brown, aiding camouflage in their murky aquatic habitats.

Xenopus frogs are carnivorous, feeding on a wide array of aquatic creatures, such as worms, small fish, insects, and even other amphibians. They are known for their voracious appetites and can be quite aggressive eaters. Unfortunately, this feeding behavior, along with their adaptability to different environments, has led them to be considered invasive species in areas where they have been introduced outside their native range.

Xenopus species have also been significant in scientific research, particularly in developmental biology and medicine. The African clawed frog was the first vertebrate to be cloned in the 1960s, and it has been a model organism in laboratories since then. Its eggs and embryos are large and easy to manipulate, making them ideal for experiments that require cell observation and manipulation.

Moreover, these frogs played a unique role in early pregnancy tests. During the mid-20th century, injecting a woman’s urine into a Xenopus frog would induce it to lay eggs if the woman was pregnant due to the presence of human chorionic gonadotropin (hCG) hormone.