Figure 4: Hypothesis of head and mouthpart morphologies in Acercaria (drawn by TB and PN).

(a) Psocodean groundpattern (also present in Hypoperlidae). (b) Permopsocidan groundpattern. (c) Thripidan groundpattern, reconstructed after the head of an adult Tubulifera, and Moundthrips. (d) Hemipteran groundpattern. Mandible: blue; maxilla: brown; anterior part of gena (mandibular lobe): yellow; posterior part of gena (maxillary lobe?): green. Ant.cl. anteclypeus; Cl.F. clypeo-frons; F. frons; Post.cl. postclypeus.