MORPHOLOGY AND DISTRIBUTION OF ANTENNAL SENSILLA IN THE POSTEMBRYONICDEVELOPMENTAL STAGES OF CIMEX HEMIPTERUS FABRICIUS

Morphology and distribution of various types of sensilla in the postem bryonic developmental stages on antennae of Cimex hemipterus were stud ied using scanning electron microscopy. Four major types of mechanosen silla and chemosensilla, i.e., serrated grooved bristles, unserrated g rooved bristles, smooth walled sensilla with pointed tip, and sensilla basiconica were identified. No sexual dimorphism was observed. The se nsillar population of serrated grooved bristles and unserrated grooved bristles increased two and six folds, respectively, while smooth wall ed sensilla with pointed tip and sensilla basiconica increased 3.5 fol ds from the first nymphal instar to males and females. A high degree o f correlation between number of various types of sensilla and differen t nymphal instars, males and females were observed. Mechanosensilla we re found distributed in all the four segments (scape, pedicel, flagell um 1, and flagellum 2) while smooth walled sensilla with pointed tip a nd sensilla basiconica were mainly confined to the two flagellar segme nts.