Fig. 7
Groups of peg-shaped sensilla outside of the scape organ based on SEM analysis. A Second (distal) basal antennomere (right antenna, flagellum to the top right) exhibiting the elevated pore of the scape organ and three groups of peg-shaped sensilla in sickle- or chevron-like formation, situated laterally (lg) and medially (mg1, mg2). Asterisks mark areas of specialized, tuberculate cuticle framing the groups of peg-shaped sensilla. The two characteristic trichoid sensilla (bottom left) are located medially and line the proximal part of the scape organ. B Lateral group of peg-shaped sensilla in detail. Note the surrounding, tuberculate cuticle. C Both medial groups of peg-shaped sensilla (indicated by dashed circles) are surrounded by tuberculate cuticle (flagellum to the bottom). Medial group 1 is sickle-shaped and directly abuts the scape organ whereas the pegs in the medial group 2 are arranged like a chevron and are located further away from the scape organ. D Detail of peg-shaped sensilla of medial group 1. The pegs only taper slightly at their tip, the circular area is clogged by polymorphic mass (arrowhead). E: Transition zone of regular and tuberculate cuticle. On the surface of the regular cuticle, scutes are well visible (compare also Fig. 7B). fl, flagellum; lg, lateral group of peg-shaped sensilla; mg1, medial group 1 of peg-shaped sensilla; mg2, medial group 2 of peg-shaped sensilla; so, scape organ; trs, trichoid sensillum