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Mallophagan family Trimenoponidae 
a heavily chitinised area from which rises the strong, downward curved hook 
at each anterior angle of the head. Slightly lateral of the clypeal region the 
anterior margin is deeply notched on each side. The flap covering the antennal 
fossa is strongly chitinised and is separated by a deep notch from the laterally 
produced posterior portion of the head. On the ventral side the wall of the 
antennal fossa is strongly chitinised, this chitinisation extending in a curve 
to the posterior margin of the head near the median line. The maxillary palpi 
are rather slender and the mouth-parts present no special characters. 
Prothorax and mesothorax closely united, the mesonotum reduced merely 
to a chitinised, transverse bar that is concealed beneath the posterior margin 
of the mesonotum. The pronotum bears a pair of broad, heavily chitinised, 
diagonal bars and the lateral margins of the mesonotum are heavily chitinised. 
Dorsally both segments bear several quite stout setae and ventrally there is 
a longitudinal series of smaller setae at the base of the coxae. 
Ahdo?nen with the pleural plates strongly developed on the third to fifth 
segments, each bearing a single long and several small setae. The lateral 
margins of the sixth to ninth segments each bear a single long seta. Tergal 
