The type locality is Baradero, Buenos Aires (Belkin et al. 1968; Knight & Stone 1977).
Larvae and pupae of Anopheles annulipalpis have been collected in large swamp marsh depressions with grasses, sunlight, pH between 5.50 and 6.79, together with larvae of Nyssorhynchus albitarsis, Aedeomyia squamipennis, Culex idottus, Culex brethesi and species of Mansonia, Psorophora and Uranotaenia. Larvae have been also collected near puddles or pools with water from the derivations of the river, which were scarcely covered with grass and aquatic macrophyta or with no vegetation and in association with Culex cuyanus and other macroinvertebrates such as Aeshnidae (Odonata), Chironomidae (Diptera), Corixidae (Hemiptera), Hydrophilidae (Coleoptera) and Hyallelidae (Crustacea).