Deliberations on the External Morphology and Modification of the Labial Segments in the Nepomorpha (Heteroptera: Insecta) with Notes on the Phylogenetic Characteristics

Figure 9

Shapes of the labial segments of the Nepidae (Ranatrinae). (a)–(e) Ranatra chinensis. (a) Lateral view (L) of the II segment, the stylet groove (gr) is partly opened at the base of the second segment, (b) the shape of the second segment, dorsal view (narrow the proximal part and a wider distal edge), the articulation of the dorsal condyle (cd) between the II and III segments on the dorsal side, (c) intercalary sclerites (is) on the III segment, the stylet groove is closed on the distal part of the second segment (II) and in the remaining segments (II and IV), (d) ventral view (V), the shape of the first segment with the midventral condyle (cv), the base of the second (II) segment in narrower than the end of the first (I) segment, the distal margin is wide, the connection between the third and fourth segments with the midventral condyle (cv) on the distal edge of the third segment, on the IV segment the oval apical plate is visible, and (e) the shape of the IV segment. Mxp: maxillary plates, Pp: posterior plate of the cranium, stb: stylets bundle.