The exocrine glands of Tetraponera worker ants

So far, a full exocrine system survey exists for the major ant subfamilies but not yet for Pseudomyrmecinae. This study provides a morphological survey of the exocrine system in workers of Tetraponera ants using the large Tetraponera rufonigra and the smaller T. allaborans, T.penzigi and T. tessmanni. We found 20 glands of which the antennal bulb gland is a new exocrine structure in ants. The cardo base gland is well-developed in all species which is striking as this gland so far was mainly found in the subfamily Formicinae. Gland size is linked with worker size, in which larger workers clearly have more cells rather than bigger cells. A study of the exocrine system in other ant subfamilies often revealed differences that are relevant for species' lifestyle and communication system. In spite of the numerous glands described in the present paper, almost nothing is known about their function in Tetraponera as surprisingly poor literature data exist on the communication system in this genus. Our study hopefully inspires researchers to perform bioassay experiments using gland extracts to fill this gap in the social biology of these ants.