Apidologie 36 (2005) 49-57
DOI: 10.1051/apido:2004068

Age-dependent morphology and ultrastructure of the hypopharyngeal gland of Apis mellifera workers (Hymenoptera, Apidae)

Jeroen Deseyn and Johan Billen

Zoological Institute, University of Leuven, Naamsestraat 59, 3000 Leuven, Belgium

(Received 19 February 2004 - Revised 20 May 2004 - Accepted 28 May 2004; Published online: 16 March 2005)

Abstract - The main secretory products of the hypopharyngeal gland are royal jelly compounds, as well as other substances such as -glucosidase. Our study of the morphology and ultrastructure of this gland in relation to worker's age clearly shows a secretory cycle within the cells, although production of secretion is asynchroneous between different cells within an acinus. Secretory vesicles appear already in 3 day old bees, while peak production is around 6 days. Thereafter, the volume of the acini as well as the number of secretory vesicles decrease and no vesicles are visible after 3 weeks of age. Foragers display degenerative structures in their cells. The hypopharyngeal gland cells of winter bees contain large numbers of secretory vesicles, that are probably stored until spring.

Key words: exocrine gland / hypopharyngeal gland / morphology / ultrastructure

Corresponding author: Jeroen Deseyn jeroen.deseyn@student.kuleuven.ac.be

© INRA, DIB-AGIB, EDP Sciences 2005