The testis follicles of three terrestrial isopods species were studied.
Two types of Sertoli cells are present in Armadillidium granulatum and Halophiloscia hirsuta.
Only one type of Sertoli cell is present in the testis follicles of Trichoniscus alexandrae.
The ultrastructure of the Sertoli cells during the spermatogenetic process was investigated.
Two septa of Sertoli cells depart from the periphery of the testis follicle to constitute an articulated compartmentalization of the follicle itself.