Comparative ultrastructure of the mandibular gland in Scaptotrigona postica ( Hymenoptera, Apidae, Meliponini) Workers and males

ABSTRACT

Differences in the ultrastructure and function of the mandibular glands in developing workers and maturemales of the meliponine stingless bee Scaptotrigona postica suggest that there are age-dependent variationsin the contents of the secretion and glandular functions. In this work, we used transmission (TEM) andscanning (SEM) electron microscopy to examine the mandibular glands of S. postica workers of differentages and compared them with those of mature males. The gland anatomy did not vary between workers andmales. However, the ultrastructure of the gland cells changed according to the worker’s age, task, and sex.The mandibular gland cells in workers and males had a well developed smooth endoplasmic reticulum andpleomorphic mitochondria, indicating that the cells were involved in lipid synthesis. However, the secretionvaried in morphology and electrondensity between workers and males, which suggested differences in itscontents and, possibly, in glandular functions.