THE MICROSPORIDIUM THELOHANIA SOLENOPSAE IN RED IMPORTED FIRE ANTS (HYMENOPTERA: FORMICIDAE) FROM LOUISIANA PASTURES

摘要

Between 25 March and 15 May 2002, red imported fire ants, Solenopsis invictae Buren, were collected from five pastures subdivided into 20 quadrants at the Rosepine Research Station in Rosepine, Louisiana. Red imported fire ants (RIFA) collected from 4quadrants were positive for a microsporidium, which was identified as Thelohania solenopsae, Knell, Allen & Hazard by light microscopic analysis of methanol-fixed and Trichrome-stained smears made from the infected insects. The range of spore morphotypes, staining patterns, morphology, and measurements were identical to T. solenopsae. This is the first evidence of T. solenopsae in natural infections of RIFA in Louisiana. The number of RIFA mounds in pastures with infected ants did not differ from the number of mounds in pastures without infected ants. Only 1.6% of mounds in quadrants treated with methoprene one year before our survey were infected, while the level of infection in the other areas was 15.4-73.3%.