The Mallophaga are described as wingless (Apterous), hemimetabolous (having a simple metamorphosis i.e. no
pupa) ectoparsites (living on the outside of their hosts) of mostly birds
but also of some mammals, there are about 2 800 species world wide. The
range in size from 0.5 to 10 mm long dorsoventrally flattened with reduced
compound eyes and no ocelli. The antennae are 3 to 5 segmented and capitate
(with a knob on the end) and recessed into the head in the Amblycera but
filiform (thin and linear) in the Ischnocera and may be modifiesd as clasping
organs in the male. Their mouthparts are designed for biting and they have
no cerci, there is some suggestion that they may have evolved from the Psocoptera
(Book and Bark Lice)
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