Cuclotogaster are a genus of chewing lice which are an ectoparasite of chickens. There are four species from the Cuclotogaster genus which are found on chickens. C. heterographus (referred to often as the "Chicken Head Louse") is the most common, and less commonly, C. burnetii, C. eynsfordi, and C. pallidus. Cuclotogaster are about 2-2.5 mm in size with an oblong grayish body and triangular head. They tend to live along the base of the chicken's feathers along the head and neck. The female lays white eggs which are attached singly to down feathers or at the base. Chickens, peafowl, pheasants, chukar can serve as hosts.