Abstract
The Koschewnikow gland is associated with the sting apparatus in the honey bee Apis mellifera Linnaeus, 1758, as a potential source of compounds used as an alarm pheromone. This study describes the histology, morphometry and ultrastructure, and chemical composition of the Koschewnikow gland in workers performing different tasks in the A. mellifera colony. The Koschewnikow gland shows well-developed globular secretory cells of class III with those of the nurse and foragers larger and in greater numbers than those of guard bees. At the ultrastructural level, the secretory cells of all worker bees are rich in mitochondria and smooth endoplasmic reticulum. Mitochondria had different ultrastructure among workers with membrane electron-dense granules in nurse and the electron-lucent halo surrounding the organelle in guard bees. Mitochondria in forager workers show degenerative features such as the disappearance of cristae, electron-lucent matrix, and accumulation of electron-dense aggregates. The chemical analyses of the Koschewnikow gland extract showed that of 23 compounds, 13 had different abundances between workers and of these, 10 were found in higher abundance in guard workers. These results suggest that the Koschewnikow gland has a different structure and chemical composition in honey bee workers engaged in different tasks.
Acknowledgments
We are grateful to the Central Apiary of Universidade Federal de Viçosa (UFV) for bee collection and the Nucleus of Microscopy and Microanalysis UFV for technical assistance.
Disclosure statement
No potential conflict of interest was reported by the authors.