Ja. Briano et al., LONG-TERM STUDIES OF THE BLACK IMPORTED FIRE ANT (HYMENOPTERA, FORMICIDAE) INFECTED WITH A MICROSPORIDIUM, Environmental entomology, 24(5), 1995, pp. 1328-1332
For 4 yr, we studied the host-pathogen relationship of the microsporid
ium Thelohania solenopsae Knell, Allen, and Hazard within field popula
tions of tile black imported fire ant, Solenopsis richteri Forel, in A
rgentina. We established and monitored 6 field plots having a high den
sity of fire ant colonies, many infected with the microsporidium. The
density of colonies, initially 162 colonies per hectare, decreased to
28 colonies per hectare. The percentage of infected colonies, initiall
y 22.4%, increased to 35.7% and was negatively associated with the den
sity of colonies but positively associated with rainfall. T. solenopsa
e was the only known natural enemy of fire ants present consistently a
nd in high levels within the plots. We suspect it is one of the main f
actors responsible for decreases in S. richteri population densities.