Can the Antarctic terrestrial midge, Eretmoptera murphyi, tolerate life in water?

Abstract

1. Early‐season flooding and ice entrapment at sub‐zero temperatures pose significant challenges to any polar terrestrial invertebrate.2. The chironomid midge, Eretmoptera murphyi, is native to the sub‐Antarctic island of South Georgia and has been introduced to the maritime Antarctic (Signy Island). While the majority of its 2‐year life cycle is spent as a terrestrial larva, it is found in habitats potentially exposed to prolonged flooding.3. The current study explored the tolerance of the larvae to extended submergence, demonstrating survival for at least 28 days, underlain by their ability to respire (oxy‐regulate) whilst submerged. To date, this ability is not known to be shared by any other terrestrial midge. Larvae also demonstrated notable anoxia tolerance whilst encased in ice, surviving for up to 28 days.4. These data indicate a capacity to survive ecologically relevant periods of submergence and/or ice entrapment, such as may be experienced in their natural habitats.