Fine structure of the hindgut and the rectal pads of Frankliniella occidentalis (Thysanoptera:Thripidae)

The fine structure of the rectal pads of Frankliniella occidentalis is described. Each pad consists of four types of cell: the principal cells, characterized by many apical infoldings of the plasma membrane and many scalariform junctions associated with mitochondria, are involved in active uptake from the intestinal lumen; the sheat cells wich surround the pad; the basal cells forming a basal cavity, and the central cells forming an axial duct in the pad. The rectal epithelium is simple and reveals structures suggesting water uptake.