Solenopsis 5. invicta

The queen is usually reproductively dominant within the colony and uses chemical cues as both primer and releaser pheromones to suppress the production or fecundity of other sexuals, inhibit reproduction by worker castes, modulate reproductive behaviors (e.g., inhibit swarming and orient swarms), attract males, regulate worker tasks and worker ontogeny, and produce host repellents in slave-making species. Considering the importance of queen semiochemicals in social hymenoptera, few queen pheromones have been chemically identified. The queens of most social hymenopteran colonies are attractive to workers, allowing them to be properly tended as well as to facilitate the dissemination of other pheromone cues. However, the retinue pheromone has been chemically identified in very few species. In the 1980s, queen pheromone components were identified in the fire ant, Solenopsis invicta [91,92], and in the Pharaoh s ant, Monomoriumpharaonis [93]. 

Although many queen-produced pheromones are actively being studied in ants, particularly in the fire ant (Solenopsis invicta) [10,105-110], chemical identifications remain elusive. However, there have been a few recent advances in ants. The queen of the slave-making species Polyergus rufescens produces de-cyl butanoate 60 that repels host workers when upsurping a colony [111]. Males of Formica lugubris are attracted to alate queens by undecane 61, tridecane 62 and (4Z)-tridec-4-ene 63 [112]. 

Glancey BM (1986) The queen recognition pheromone of Solenopsis invicta. In Lofgren CS, Vander Meer RK (eds) Fire ants and leaf-cutting ants biology and management. Westview Press, Boulder, p 223... 

Phillips, S.A., Jr. D.M. Clabom, and O.F. Francke. 1984. Comparison of aerial application and single-mound drenches of fenvalerate against the red imported fire ant, Solenopsis invicta Buren, in Texas. Southwestern Entomol. 9 164-168. 

Mirex (dodecachlorooctahydro-l,3,4-metheno-2H-cyclobuta [tv/] pentalene) has been used extensively in pesticidal formulations to control the red imported fire ant (Solenopsis invicta), and as a flame retardant in electronic components, plastics, and fabrics. One environmental consequence of mirex was the severe damage recorded to fish and wildlife in nine southeastern states and the Great Lakes, especially Lake Ontario. In 1978, the U.S. Environmental Protection Agency banned all further use of mirex, partly because of the hazards it imposed on nontarget biota. These included ... 

It had been already reported, that the venom of the fire ant Solenopsis invicta is composed of 2-methyl-6-alkyl- or 2-methyl-6-alkenylpiperidines,the carbon chain of which has an odd number of carbon atoms in the range of 11 to 17 [ 115, 116]. Recently, Deslippe and Guo [120] reported that in workers of S. invicta from Texas the relative abundance of each alkaloid was highly correlated with worker size as well as with the ratios of saturated to unsaturated alkaloids. Moreover, young and old workers produced less venom than ants of intermediate age... 

Laboratory studies have indicated that ozone at l%Mg/m (0.10 ppm) was lethal to adult houseflies Musca domestica L.) and caused them to lay fewer eggs. Two cockroach species Paraplaneta americana L. and Nauphoeta cinerea Oliver) and the red fire ant Solenopsis invicta Buren) were exposed to ozone at SSSug/m (0.30 ppm) for up to 10 days. There was no unusual mortality or evidence of direct injury to individual insects. The fire ant workers were stimulated to migrate inside their nest initially, but further observations indicated no disruption of social behavior. These reports do not suggest that free-ranging insects would be directly affected by ambient concentrations of ozone in natural ecosystems or agroecosystems. 

Thirdly let ns consider ants. They are a social gronp and may forage across snbstantial distances as a group. Ants lay down a molecnlar trail for other ants to follow. The molecnles involved are termed trail pheromones. Now there are many species of ants and they nse different trail pheromones for the obvions reason of being able to follow the right trail as opposed to that of some other species. That for the hre ant, Solenopsis invicta, is a hydrocarbon of moderate complexity ... 

Two examples of the remarkable potency of avermectin Bj are its LD9Q of 0.02 to 0.03 ppm against the two-spotted spider mite, Tetranychus urticae, when applied to bean plants as a foliar spray and its control of the red imported fire ant, Solenopsis invicta, when applied as a bait at a level as low as 25 to 50 mg per acre (19). 

Venoms from the fire ants Solenopsis invicta and 5. geminata are free of detectable histamine but possess histamine-release activity. This activity can account for the edema, itch, redness, warmth, and possibly the pain and burning sensations resulting from fire ant stings. And it can be attributed to the piperidines which constitute the major component of the venom. It has actually been proved that 6-methyl-2-n-undecylpiperidines (Ic and Id), components of S. geminata, possess the histamine-release activity (75). Due to some of the above-mentioned various activities the piperidine alkaloids play roles as defensive compounds. In addition to 2-alkyl-6-methylpiperidines, their N-methyl derivatives (3) are found in S. pergandei, S. carolinensis, and S. conjurata, and 1-piperideine derivatives (6 and 7) in S. sp. A (Puerto Rico) and S. xyloni (Table I). 

Isidore N., Romani R., Velasquez D., Renthal R., Bin F. and Vinson S. B. (2000) Antennal glands in queen and worker of the fire ant, Solenopsis invicta Buren first report in female social Aculeata (Hymenoptera, formicidae). Insectes Soc. 47, 236-240. 

Baird D. S. (2001) Semiochemical studies on the red imported fire ant (Solenopsis invicta), the tarnished plant bug (Lygus lineolaris) and the varroa mite (Varroa destructor). In Chemistry. Simon Fraser University Burnaby. 

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