The genus Somaphantus Paine, 1914 is a little known genus previously represented by two species: S. lusius Paine, 1914 found on a guinea fowl, Numida meleagris macroceras Erlanger; and S. spencei Emerson, 1958 found on the Indo-Chinese Green Peafowl, Pavo muticus imperator Delacour. S. spencei is known to live inside the quills of the primaries. The elongated body form with short abdominal sternal and tergal plates for both S. Lusius and the species herewith described as new are characters which cause us to believe that quills of primaries represent the normal habitat for all species of the genus. These characters are also typical of species of Longimenopon and certain species of Actornithophilus which live in this habitat in the petrels and shorebirds, respectively. Very few specimens of Somaphantus and Longimenopon have been collected, probably because few collectors suspect lice are to be found in this habitat.