Which group of mammals is covered in protective keratin scales?

Pangolins are the group of mammals covered in protective keratin scales.

Pangolins belong to the order Pholidota and the family Manidae. Their large, overlapping scales cover much of the body and act as armor. The scales are made of keratin, the same tough structural material found in human fingernails, hair, and the claws of many mammals.

When threatened, a pangolin can curl into a tight ball, shielding its soft underside and face with its armored back and tail. This defense explains the name pangolin, which comes from a Malay word associated with rolling up. Pangolins are sometimes called scaly anteaters, but they are not closely related to true anteaters.

Armadillos are another common mix-up. Armadillos also have protective body armor, but their plates are made from bony dermal tissue covered by keratin, not the same type of overlapping keratin scales found on pangolins. Pangolins are mostly nocturnal and use long, sticky tongues to collect ants and termites.