Distribution: The Holarctic species shows a wide distribution area, extending throughout Europe (except the Iberian Peninsula) Asia Minor, the Middle East, Siberia and North America (Mohrig 1969, Cranston et al. 1987, Schaffner et al. 2001, Becker et al. 2003).

Habitat: O. communis is a sylvatic species (Mohrig 1969, Briegel 1973, Schaffner et al. 2001). Its breeding places are primarily found in pine forests and are less abundant in deciduous woods (Rettich et al. 1978). They include ponds, ditches, mires, peat bogs or rock pools (Schaffner et al. 2001) in lowlands or in mountainous regions (Mihályi 1959), mainly free of vegetation with a dense layer of leaf litter (Becker et al. 2003). Larvae are encountered from more or less shaded habitats (Cranston et al. 1987) and seem to prefer acidic water (Mohrig 1969, Becker et al. 2003).

Biology: O. communis shows one generation per year (Mohrig 1969, Cranston et al. 1987). Eggs are laid on the dry ground, under leaf litter or in mosses (Mohrig 1969). In southern countries larvae already hatch in autumn (Mohrig 1969); in northern or mountainous regions the species overwinters in the egg stage (Schaffner et al. 2001) and first instars hatch in late winter (Rettich et al. 1978). Hence the species is qualified as "snow-mosquito" (Schaffner et al. 2001). Adults are present in spring and summer (Mohrig 1969, Rettich et al. 1978, Schaffner et al. 2001).

Adults: Females feed on birds and mammals, including humans (Cranston et al. 1987, Schaffner et al. 2001). They primarily attack at dawn or at dusk, and even during daytime in dense forests (Mohrig 1969, Becker et al. 2003). They seldom leave the forest and enter dwellings, but can scatter up to 23 km; some females have been found to be naturally infected by several viruses such as Batai and Inkoo, as well as by Tularaemia; in laboratory conditions it is able to transmit the Tahyna virus (Schaffner et al. 2001).