Scapteriscus chaetica (Keil, 1999)

Kostromytska, Olga, Scharf, Michael E. & Buss, Eileen A., 2015, Types and functions of mole cricket (Orthoptera: Gryllotalpidae) antennal and palpal sensilla, Florida Entomologist 98 (2), pp. 593-605 : 596

S. chaetica

These sensilla were the most abundant on mole cricket antennae (up to 120 per segment) ( Table 2). The surface of these sensilla had transverse ridges with no evidence of wall pores ( Fig. 3 A, B ). Three types of s. chaetica were observed based on their size and distribution pattern on the antennae. Type I were relatively large s. chaetica (~100 μm long and 5 μm wide) and they created ring–like transverse patterns (relative to the antennal axis) at the base of an antennal segment ( Fig. 1 B, D and Fig. 3 C ). They were relatively straight, in contrast to other types of sensilla which were medium (type II) in size and curved toward the following antennal segment. Medium s. chaetica (~60 μm long and 3 μm base diameter) usually were observed in the rows at the distal part of the segment. The smallest s. chaetica (type III) were distributed evenly on the antennal segment (40 μm long and 2 μm base diameter). Wall pores were not observed on the s. chaetica and TEMs showed that the larger s. chaetica (types I and II) were filled with dense material with no evidence of dendritic processes in the lumen ( Fig. 4 A, B ). However small (type III) s. chaetica were innervated ( Fig. 4 C, D ).

Figures

Fig. 3. Sensilla chaetica, the most abundant sensilla on S. vicinus antennae. Antennal surface of S. vicinus with s. chaetica positioned in the flexible sockets (mag- inifaication ×9k) (A), aporous ridged surface of the sensillum (magnification ×6k) (B), antennal segment and different types of sensilla,s. chaetica types I and II (schI and II), arranged into transverse patterns,type III s. chaetica (sch III) are small and evenly distributed on the flagellomere (×600) (C). Row of s. basioconica (sb) and s. trichodea (si) (C) usually observed on the apical portion of the flagellomere.

Fig. 1. SEM photos of the flagellum mid-section of N. hexadactyla (A), S. abbreviatus (B), S. vicinus (C) and S. borellii (×140) (D).

Fig. 4. Transmission electron micrographs of s. chaetica type I and II (A, B) which are not innervated and are dense inside with thick sensillum wall (sw), type III s. chaetica have less dense sensillar lumen (sl) and are innervated with 4 dendrites (d) (C, D).