The present study was conducted on male prawn Penaeus semisulcatus De Haan 1844, to assess the spermatophore formation around the chambers containing sperm mass in distal vas deferens and terminal ampoule. For the study, the technique recommended by Felgenhauer (1987) for preparing crustacean tissues for scanning electron microscopic studies was used. The transverse sections of the terminal ampoule and vas deferens have been studied in detail using Scanning Electron Microscopy. The study showed that the vas deferens is formed of three chambers and three spermatophoric layers and the terminal ampoule is formed of three chambers and five spermatophoric layers. The sperm mass accumulated in the three chambers surrounded by five spermatophoric layers is discussed in detail.

Penaeus semisulcatus, vas deferens, terminal ampoule and spermatophoric layers