Females are not anthropophilic and can be found as well as in mountain creeks from sea level to 4,700 m of altitude (Wygodzinsky & Coscaron 1989). ''Gigantodax'' is a peculiar genus, showing the greatest diversity among the Prosimuliini genera, with synapomorphies in imago and preimaginal stages that help to differentiate species in this genus from other genera. The unusual morphology of the respiratory filaments in the pupal stage is useful in differentiating species.〔

...the first phylogenetic hypothesis for the 13 Southern Hemisphere genera of Simuliidae is proposed, through a cladistic approach. In order to investigate the position of those genera representatives of five Northern Hemisphere genera were also included in the analyses as outgroups. The study was based on a data matrix with 33 terminal taxa and 119 morphological characters of adult, pupa and larva. The phylogenetic analysis under equal weights resulted in four most parsimonious trees, with similar topologies and 349 steps...〔() Preliminary considerations on phylogeny of Simuliidae Genera from Southern Hemisphere (Insecta, Diptera)〕