All Paraguayan specimens have been taken at ground level, despite simultaneous trapping efforts in trees. This suggests that they have at least a partially terrestrial existence. The prehensile tail and digit arrangement indicate that they are adapted for climbing (Smith, 2009).
No data unequivocally referring to this species is available.
Massoia and Fornes (1972) stated that Marmosa agilis chacoensis in Rio Grande do Sul, Brazil, gave birth to litters of up to 12 young. Given that the number of teats is 9, the possibility of misidentification means that the data must be treated with caution (Smith, 2009).