Knowledge about the role of the nest environment in the life cycle of laelapine mites associated with neotropical small mammals is unclear because nests have rarely been collected. Here we use infestation data to make predictions about host–mite ecology and examine the nests of the host to assess the validity of these predictions. Spool-and-line method was used to track Cerradomys subflavus nests. We found that: the structure of mite populations infesting the body of C. subflavus, was strongly biased toward the reproductive female stage; recaptured hosts were re-infested with laelapine mites at different rates; and female hosts were not more highly infested than males. We found strong evidence of nidicoly with both, Gigantolaelaps vitzthumi and Androlaelaps fahrenholzi. The G. vitzthumi was more abundant in the nests of female rodents and with both these mite species, we encountered males and immature mites in the nests, although not in the host fur.