ABSTRACT
Head large, triangular in frontal view, lying flush to thorax, as wide as apex of thorax, sharply constricted behind eyes, hypognathous; surface smooth or rugose-punctate. Antennae with eleven antennomeres; mostly short, not extending beyond thorax in most species; commonly filiform, somewhat serrate or clavate, pectinate only in Ctenidiinae; inserted under frontal ridge, close to base of mandibles. Clypeus distinct, small; labrum prominent, entire; mandibles short, stout, somewhat curved, apices acute or bifid. Maxillary palpi long with four palpomeres, apical palpomere large, securiform, scalene, cultriform, or malleiform. Gular process present; mentum trapezoidal; ligula prominent, cordiform; labial palpi with three palpomeres, apical palpomere triangular. Eyes lateral, large, well developed, shape oval, round, to almost square, anterior margin behind antenna emarginate in some; eye facets fine to coarse.
