 Chewing lice are also flattened and can be slightly larger than sucking lice , ranging in length from 0 @.@ 5 to 6 mm ( 0 @.@ 02 to 0 @.@ 24 in ) . They are similar to sucking lice in form but the head is wider than the thorax and all species have compound eyes . There are no ocelli and the mouthparts are adapted for chewing . The antennae have three to five segments and are slender in the suborder <unk> , but club @-@ shaped in the suborder <unk> . The legs are short and robust , and terminated by one or two claws . Many lice are specific to a single species of host and have co @-@ evolved with it . They are usually cryptically coloured to match the fur or feathers of the host . 
