The occurrence of apical labial sensilla in the Aleyrodidae and evidence for a contact chemosensory function
1989
Walker, G.P. | Gordh, G.
Scanning electron microscopy of the apex of the labium of six species of whitefly [Aleurothrixus floccosus (Maskell), Aleyrodes spiraeoides Quaintance, Bemisia tabaci (Gennadius), Dialeurodes citri (Ashmead), Parabemisia myricae (Kuwana), and Trialeurodes vaporariorum (Westwood)], revealed that all possess seven pairs of sensilla symmetrically positioned on either side of the labial groove. Transmission electron microscopy revealed that in P. myricae, sensilla 1, 5, 6 & 7 are innervated each by a single dendrite, sensilla 2 & 4 are innervated by three dendrites each, and sensillum 3 is innervated by four dendrites. Multiple innervation of sensilla 2, 3 & 4 suggests a chemosensory or mechano-chemosensory function. Longitudinal sections of sensilla 2 & 4 showed that the sensilla were hollow with an apical pore, providing further morphological evidence for a chemosensory function. One dendrite appeared to end at the base of sensillum 2, suggesting that at least sensillum 2 has a dual mechano-chemosensory function. The presence of contact chemoreceptors on the labial tip may help explain how P. myricae can discriminate between hosts before probing.
显示更多 [+] 显示较少 [-]