Abstract: Microstructure and ultrastructure of the spermatheca of g rasshopper Oedaleus infernalis Saussure (Orthoptera： Acridoidae ) were investigated with light microscopy and transmission electron microscopy. The unpaired spermatheca can be subdivided into a multiple coiled tube and a bean-shaped terminalsac. The spermathecal wall from inside to outside consists of cuticula intima, epithelium layer, basal lamina and muscle layer. The epithelium layer is comprised of a layer of epithelial cells with a distinct apical microvilli border, a layer of ductule cells and gland cells, with the epithelial cells heavily intercalated with one another and slender projections extending between the ductule cell and the gland cell to basal lamina and folded. The basal plasma membrane of gland cell and epithelial cells form a huge labyrinth through extensive folding. The ductule cell transports secretion of gland cell. The gland cells show structures typical for secretion cell: ER, Golgi body and different size vesicles. Every gland cell contains a cellular cavity, which is coated with a microvilli border and connected with secretion ductules. By secretion ductules , the cellular cavity was connected with spermathecal lumen. In the outer layer is muscle layer attached to basal lamina. There are differences of structure in terminal sac and tube regions. Significant differences in ultrastructure of spermathecal gland cell before and after copulation were observed.

Key words: Oedaleus infernalis, spermatheca, microstructure, ultrastructure