The activity of Aspergillus ochraceus (fungi) on replete females of Rhipicephalus sanguineus (Acari: Ixodidae) in natural and experimental conditions. 
Aspergillus ochraceus Wilhelm was isolated from Rhipicephalus sanguineus (Latreille) ticks infected under natural conditions, and developing an illness characterized by absence of oviposition, mummification and death.  From the histological sections, it is deduced that A. ochraceus colonized the ticks via the anus, as posterior gut and Malpighian tubules are invaded.  The experimental inoculation was carried out on replete female ticks; a disease alike to that observed in naturally infected ticks developed only when specimens are placed under a relative humidity near saturation.