|Briano, Juan - BIOCONTROL LAB ARGENTINA|
|Calcaterra, Luis - BIOCONTOL LAB ARGENTINA|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: April 6, 1998
Publication Date: N/A
Technical Abstract: Solenopsis (Labauchena) daguerrei (Santschi) is a parasitic ant of imported fire ants. This parasite produces no worker caste, and is totally reliant on its host colony for its care. Having no worker caste, only reproductive males and females represent this species. S. daguerrei will attach, or yolk, themselves to queens of the black and red imported fire ants, Solenopsis richteri and S. invicta, respectively, and divert resources fro the host queen(s). In addition, the host colony also feeds and maintains the brood of S. daguerrei. Thus, S. daguerrei is a potential stress factor of fire ant colonies. This parasite is found in South America, and is being held in quarantine in the United States at the Center for Medical, Agricultural, and Veterinary Entomology in Gainesville, Florida. Field studies and observations of the impact of S. daguerrei on S. richteri were conducted in sites located in Buenos Aires Province, Argentina. Mean percent parasitism from pastures located at 21 sites (San Eladio, Argentina) was 5.1% (range: 1.2 to 23.7%; total 2,580 S. richteri colonies examined). Mound densities were 33% less in sites with S. daguerrei, where there were 161 # 14 (# std. err.) mounds/ha, while parasite-free sites had 239 # 15 mounds/ha. The number of S. richteri queens per colony was 47 % less in parasitized colonies (parasitized = 2.9 # 0.5, range: 1 - 40 versus non-parasitized = 5.5 # 2.0, range: 1 - 180). In addition, both female and male S. richteri alates were observed in parasitized colonies. This is in contrast to reports by Silveira-Guido et al. (1973) who did not observe alates in parasitized S. richteri colonies. There was a 3:1 female to male sex ratio for S. daguerrei from excavated S. richteri colonies.