Frons of head of Melophorus showing structures mentioned in this monograph: AS antennal scape AT apical tooth BT basal tooth CI compound eye CS clypeal psammophore, consisting of a fringe of setae (nb. only those on RHS of head labelled) FC frontal carina FT frontal triangle M mandible OT ocellar triangle, consisting of three ocelli (simple eyes) T torulus TP tentorial pit; 2, 3, 4, tooth sequence commencing from the apical tooth.