Deltoxenos cf. bequaerti, male, cephalotheca, SEM micrographs A frontal view B mouthparts. Abbreviations: a – vestigial antenna, at – antennal torulus (rudiments of antennal torulus), cll – clypeal lobe, cls – clypeal sensillum, coe – compound eye, dlf – dorsal field of labral area, es – epistomal suture, fi – frontal impression, fr – frontal region, gn – gena, hyp – hypopharynxgeal protuberance, md – mandible, mdb – mandibular bulge, mdc – mandibular capsule (clypeal origin), mdt – mandibular tooth, mx – vestige of maxilla (maxilla), mxb – maxillary base (at mandible base), ob – occipital bulge, os – mouth opening, paa – periantennal area, pom – postmentum, prm – praementum, sra – sensillum of vestigial antenna, ssf – supra-antennal sensillary field, sssf – sensillum of supra-antennal sensillary field, vlf – ventral field of labral area.