Chewing lice are small insects that lack wings and feed off of birds and mammals. They have short, concealed antennae, and they lack cerci.

Chewing lice are parasites that feed off of the feathers of birds or the hair of mammals. None of them attack humans directly, though they do attack domesticated animals.

Chewing lice live on their hosts their entire life. They can be transferred to another host by direct contact only.

There are two suborders in Mallophaga, and they are seperated by the structure of their antennae and maxillary palps. The two suborders are Amblycera and Ischnocera.