Ultrastructural, histological and histochemical characteristics of the epithelial wall of the seminal vesicle of mature Scaptotrigona xanthotricha moure males (Hymenoptera, apidae, meliponini)

ABSTRACT

The seminal vesicles of mature Scaptotrigona xanthotricha males were investigated using light microscopy, histochemistry and transmission electron microscopy. The globular seminal vesicles were ~450 ìm in diameter and consisted of a sperm-filled lumen and a single layer of epithelium surrounded externally by a muscular sheath. The mitochondria-rich epithelial cells had many inclusions in the basal region. These inclusions were relatively large and contained membranous structures similar to myelin figures. The epithelial cells of the seminal vesicle showed none of the features characteristically associated with a secretory function, which suggested that the material in which the spermatozoa were immersed in the vesicle lumen was produced elsewhere along the ducts and/or during sexual maturation of the males. Spermatozoa were occasionally seen inside the inclusions, which suggested a possible spermiophagic activity for this epithelium.