Recruitment and trail communication in two species ofMessorants (Hymenoptera, Formicidae)

Abstract

Behavioural patterns and chemical signals mediating recruitment communication of the harvesting ants M. minor and M. wasmanni were studied. Recruitment towards a food source was investigated in the laboratory. Bioassays showed that successful scouts induce nestmates to leave the nest by substances from Dufour's gland. This gland was also found to be the source of the chemical trails by which foragers reach newly discovered feeding sites. Glandular secretions from the last abdominal tergites as well as from the poison gland induced typical alarm reactions, suggesting their involvement in alarm communication and recruitment towards a source of danger. Production of stridulations by scouts and recruited foragers was also recorded on the food items under both field and laboratory conditions. The possible role of such vibrational signals in foraging communication is discussed. Finally, a comparison of the communication systems employed by both species was made and some ecological implications are discussed.

Trail communication in twoMessorspecies,M. meridionalisandM. foreli(Hymenoptera: Formicidae)

“…This is consistent with previous studies on M. structor (Hahn & Maschwitz 1985), M. bouvieri (Jackson et al 1989(Jackson et al , 1991, M. capitatus (Grasso et al 1998), M. minor and M. wasmanni (Grasso et al 1999). …”

Worker size polymorphism and ethological role of sting associated glands in the harvester ant Messor barbarus

“…Within the Pheidolini tribe to which belongs the genus Messor, the glandular source of the trail pheromone is nevertheless highly variable. While the poison gland contains the trail substance in most Pheidole (Hölldobler and Möglich, 1980;Ali et al, 1989) and all Aphaenogaster species (Hölldobler et al, 1978;Attygalle et al, 1998), the Dufour gland secretion releases trail following responses in all studied Messor species (Hahn and Maschwitz, 1985;Coll et al, 1987;Jackson et al, 1991;Grasso et al, 1998Grasso et al, , 1999 excepting in M. pergandei (Blum, 1974). We here found that, as for M. structor (Hahn and Insectes soc.…”

“…Vol. 47, 2000 Research article 387 Maschwitz, 1985), M. capitatus (Grasso et al, 1998), M. minor and M. wasmanni (Grasso et al, 1999), the Dufour gland secretion of M. barbarus acts both as a recruitment pheromone which induces numerous nest exits and as an orientation substance which elicits a marked trail-following response over long distances. The interspecific variability in the ethological role of the Dufour gland observed within the Pheidolini tribe could be related to the foraging ecology of ant species.…”

“…We demonstrate that, in M. barbarus, the secretion of the poison gland elicits aggressiveness among nestmates. A possible role of poison gland in alarm and defence has also been suggested for five other Messor species though not based on quantitative data (Hahn and Maschwitz, 1985;Coll et al, 1987;Grasso et al, 1998Grasso et al, , 1999. Besides its role in alarm and defence, the poison gland secretion may be a gustatory repellent when contacted orally or ingested by predators.…”

“…In Pogonomyrmex species, the short-lived secretion of the poison gland serves as a recruitment pheromone and an orientation cue while the Dufour gland secretion produces additional orientation signals used on longer-lasting trails (Höll-dobler and Wilson, 1970). On the other hand, in most but not all species of the genus Messor [M. structor (Hahn and Maschwitz, 1985); M. bouvieri (Jackson et al, 1991), M. capitatus (Grasso et al, 1998), M. minor and M. wasmanni (Grasso et al, 1999), but not M. pergandei (Blum, 1974)] it is the Dufour gland which is responsible for the production of the trail pheromone and which contains both recruitment and orientation substances, while the poison gland secretion only elicits a weak trail-following response.…”