Ultrastructure of sensory receptors on the antennae of Oryctes elegans Prell (Coloeptera: Scarabidae)

Oryctes elegans is one of the economically important pest of palm trees in Saudi Arabia. Chemoreceptors are very important organs for mating, feeding or oviposition in insects. We described the morphology ultra structure and description of antennae among males and females using scanning electron microscopy. Observation have been described determined that the antennae of O. elegans were lamellate type and composed of nine segments. There were three types of trichoid sensilla found on the antennae. These were elongated, curved and articulate, respectively. Fourth type was placoid sensillae concentrated on the lateral segments of antennae. These sensillae were abundant distributed on pedicle and the 1st flagellomeres. Sensillae found on females and males antennae were similar but the antennal segments of males were thinner than females.