Comparative Analysis and Systematic Mapping of the Labial Sensilla in the Nepomorpha (Heteroptera: Insecta)

Figure 21

Types and sizes of the sensilla of the Naucoridae: Limnocorinae (Limnocoris lutzi). (a) MPS are numerous and distributed in rows over the IV segment (dorsal view). (b) PAS (no. 1–12) are located on the labial tip (SFL). (c) TRS1 (four) and TRS2 (one) are situated on the ventral side (V) in one row near the apex of the IV segment; MPS are also numerous ventrally and distributed in rows. (d) CH2 are less numerous and sparsely distributed over the ventral surface of the III and II segments. (e) TRS2 (three) are distributed separately on the distal edge of the III segment, MPS are less numerous and sparsely situated on the dorsal surface of the III segment, COS are situated on the IV segment, and on the surface of the III segment there are numerous, characteristic plates (generally unidentified structures, PLE-type). (f) Two (or four) COS-p are visible on the external distal edge of the II segment, and one is situated internally closer to the labial groove (Figure 21(f)). Two the COS-d are situated in the middle of the II segment on the proximal edge.