The zone of mature spermatozoa in the testis of Salamandra salamandra (L.) (Amphibia, Urodela).

The zone of mature spermatozoa in the testis of the european fire salamander, Salamandra salamandra, consists of numerous lobules embedded in a vascularized connective tissue. Most of the lobule boundary cells show features of SH-secreting cells (an increased amount of smooth ER, globular mitochondria with tubular cristae), whereas other retain a fibrocytic appearance. The mature spermatozoa within the lobules seem to be at least partly phagocytized and digested by the often highly vacuolized Sertoli cells. Lobules open into efferent ductules lined by a monolayered epithelium, whose cells are highly interdigitated. The capillaries of the interlobular connective tissue possess enlarged luminal and basal surfaces.