Three cold-adapted mosquitoes of the species Culiseta annulata were found in southern Iceland this autumn, ending the country’s long-standing status as one of the few places on Earth without mosquitoes and raising questions about Arctic ecology and climate change.

Iceland, long regarded as one of the few remaining mosquito-free nations alongside Antarctica, has recorded its first confirmed wild mosquito sightings this year. Scientists at the Icelandic Institute of Natural History identified two female and one male Culiseta annulata from a garden in the Kjós valley, north of Reykjavík, in mid-October 2025.

The species Culiseta annulata is known for its cold-tolerance and ability to overwinter in sheltered buildings or containers, traits that may aid survival in Iceland’s previously inhospitable environment.

Until this discovery, Iceland’s combination of short summers, frequent freeze-thaw cycles in wetlands, and geographic isolation had prevented mosquitoes from establishing permanent populations. The finding now removes Iceland’s long-held distinction and leaves Antarctica as the only landmass reliably free of mosquitoes.

Researchers caution that while the presence of these mosquitoes is significant, it is not yet clear whether they have formed a self-sustaining population in Iceland. It remains to be determined if they can survive the winter, breed in local habitats, and expand their range.

Nonetheless, the discovery is already being viewed as a signal of ecological change in the Arctic. Warming temperatures, increasing freight traffic, and shifting insect-dispersal pathways may be combining to allow species previously excluded from Iceland’s cold climate to gain a foothold.

Source: Earth.com, ScienceNews, Mbl.is