Rossomyrmex, the Slave-Maker Ants from the Arid Steppe Environments

Table 1

Some traits about the biology of the three Formicini slave-making genera.

	Rossomyrmex	Polyergus	F. sanguinea group
Parasitism	Obligate	Obligate	Facultative
Recruitment	Transport of workers to the target nest	Group recruitment	Group recruitment
Raiding	(i) No use of semiochemicals; (ii) Rare fights; (iii) Host-nest exploitation extended in time (2 days); (iv) Not reraiding on the same nest; (v) Average 2 raids/year; (vi) Slaves do not participate	(i) Alarm semiochemicals; (ii) Some fights; (iii) Intense and quick host-nest exploitation (<1 h); (iv) Reraiding on the same nest; (v) Maximum 50 raids/year; (vi) Slaves do not participate	(i) No use of semiochemicals; (ii) Intense fights; (iii) Intense host-nest exploitation (several hours); (iv) Reraiding on the same nest; (v) More than 26 raids/year; (vi) Slaves participate
Mating	(i) Sexual calling; (ii) Return to the mother nest after mating; (iii) Polygamous male; (iv) Single female mating: monandry (with some exceptions)	(i) Mating on the ground or even during raids; (ii) Variable. Return to the mother nest after mating, fly away; (iii) ?; (iv) Single female mating: monandry (with some exceptions)	(i) Nuptial flight, intranidal mating; (ii) Return to the own or conspecific nest after mating; (iii) ?; (iv) Multiple mating: polyandry
Sex allocation	Female biased	?	Female biased
Foundation	(i) Usurpation; (ii) New queen enters a host nest alone; (iii) repellent substance from Dufour’s gland (Tetradecanal)	(i) Usurpation; (ii) New queen enters a host nest during a raid; (iii) Appeasement substance from Dufour’s gland (decyl butanoate)	(i) Variable (adoption, usurpation); (ii) New queen enters a host nest during a raid; (iii) Substances from Dufour’s gland of unknown effect (n-decyl acetates)