ARS | Publication request: The fire ant (Hymenoptera: Formicidae) pathogen, Vairimorpha invictae (Microsporidia: Burenellidae), not detected in Florida

Submitted to: Florida Entomologist
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 3, 2012
Publication Date: March 4, 2012
Citation: Oi, D.H., Valles, S.M., Porter, S.D. 2012. The fire ant (Hymenoptera: Formicidae) pathogen, Vairimorpha invictae (Microsporidia: Burenellidae), not detected in Florida. Florida Entomologist. 95(2):506-508.

Interpretive Summary: Surveys were conducted by scientists at the USDA-ARS Center for Medical, Agricultural, and Veterinary Entomology to search specifically for the microsporidian pathogen Vairimorpha. invictae in red imported fire ants, in the U.S. This pathogen is associated with colony decline and reductions in fire ant populations in S. America and thus is a promising biological control agent. As such, it is necessary to determine its presence or absence in the U.S. V. invictae was not detected in any of the 1,016 nest samples collected in 21 counties located in five states. A majority of samples (83%) originated from Florida. Despite the absence of V. invictae, another microsporidian pathogen of fire ants that is already established in the U.S, Kneallhazia solenopsae, was detected in 14.5 % of the samples. Based on our sampling, V. invictae is currently not established in the U.S. V. invictae represents an additional natural enemy that could be imported from South America for the classical biological control of the invasive red imported fire ants.

Technical Abstract: Surveys were conducted to search specifically for the microsporidian pathogen Vairimorpha. invictae in red imported fire ants, Solenopsis invicta, in the U.S. This pathogen is associated with colony decline and reductions in fire ant populations in S. America and is considered to be a promising biological control agent. As such, it is necessary to determine its presence or absence in the U.S. V. invictae was not detected in any of the 1,016 nest samples collected in 21 counties located in five states. A majority of samples (83%) originated from Florida. Despite the absence of V. invictae, another microsporidum, K. solenopsae, was detected in 14.5% of the samples. Based on our sampling, V. invictae is currently not established in the U.S. V. invictae represents an additional natural enemy that could be imported from South America for the classical biological control of S. invicta.