Solenopsis geminata

Jaffe, K., and Puche, H., 1984, Colony-specific territorial marking with the metapleural gland secretion in the ant Solenopsis geminata (Fabr), J. Insect Physiol., 30 265. 

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). 

Cabrera, A., Williams, D., Hernandez, J.V., Caetano, F.H. and Jaffe, K. (2004). Metapleural- and postpharyngeal-gland secretions from workers of the ants Solenopsis invicta and S. geminata. Chem. Biodivers., 1, 303-311. 

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