Seven nests of T. fuscus Emery, 1834 have been studied for their structure. These nests, which opened at the soil surface, had two to four chambers located one above the other. Externally all of these nests presented a heap of brownish-yellow debris that was constituted basically by remains of vegetable material. The total nest population was, on average, 1,048 individuais. The diel pattern of foraging of this species was studied for four consecuti ve months on two nests. This activity occurred predominantly in the night period, and the workers transported, mainly, dry vegetation to the nest.
Attini; fungus-growing ants; caracterization of nest; foraging activity