Ultrastructure and dendritic innervations of antennal sensilla of adult small brown planthopper, Laodelphax striatellus

The morphology and distribution map of antennal sensilla of adult small brown planthopper have been revealed (Fu et al. 2012), and this report is the subsequent work to reveal the dendritic innervations of the peripheral sensory system of this species, aiming to provide strong evidences for further electrophysiological and behavioral researches. The ultrastructure and dendritic innervations of antennal sensilla of male and female macropterous and brachypterous small brown planthopper were revealed by transmission electron microscopy. The results did not show any difference between the four types of adults, and the innervations of the 7 types of presumed sensilla are roughly as follows. Sensilla placodea are innervated by groups of sensory neurons, dendrites branched, possess numerous pores, while sensilla trichodea possess one to three sensory neurons each, dendrites unbranched and their pores are rarely to be sectioned. Sensilla chaetica and the single böhm bristle are innervated by one neuron whose dendrite ends in a tubular body at the base of the hair shaft. Sensillum campaniformium I possesses one sensory neuron, dendrite ends in a tubular body. Sensory peg I and sensory peg II housed by the one sensillum coeloconicum possess different innervations, and are innervated by one and four sensory neurons respectively. The three sensilla basiconica are innervated by three sensory neurons each.