Scanning electron microscopy of cuticular sensory structures on the legs of Micronecta haliploides (Horvath, 1904) and Hydrometra greeni (Kirkaldy, 1898) (Hemiptera: Heteroptera)

Abstract

Structures on the legs of two hemipteran bugs, Micronecta haliploides (Horvath, 1904) and Hydrometra greeni (Kirkaldy, 1898), belonging to family Micronectidae and Hydrometridae of two infra orders Nepomorpha and Gerromorpha, respectively were investigated using scanning electron microscopy. Both species have a distinctive leg structure bearing specialised cuticular sensory structures. In the study, the sensilla were classified into five basic types: sensilla trichoidea, sensilla basiconidea, sensilla placoidea, porous circular sensilla and sensilla bell mouthed. These sensilla were further differentiated on the basis of shape, size, number, flexibility and type of socket attached. A total of 26 types of sensilla in the legs of these two species were observed. M. haliploides showed 18 types of sensory structures and H. greeni 8 types. A specific morphological structure of the porous circular sensilla was observed and found to be unique.