#25: Antarctic Midge

Litinsects #25: Antarctic Midge

Are you ready for a truly crazy-sounding fun fact? The Antarctic midge, a fly that measures 2-6 mm, is the largest fully terrestrial animal found on the entire continent of Antarctica!

It might sound crazy but it’s true! Animals that you immediately associate with the continent, such as penguins and seals, are not purely terrestrial because they spend a large portion of their lives in the water.

The islands surrounding Antarctica are home to a few other invertebrates including mites, springtails, earthworms, and nematodes but the midge is special because it is ENDEMIC to Antarctica, meaning it is found nowhere else on earth.

These tiny guys are FLIGHTLESS. It is thought that they have evolved to have reduced wings to prevent being blown away by wind

They feed on terrestrial algae, moss, detritus, and microorganisms

Of all insect genomes sequenced so far, the Antarctic midge has the smallest, at 99 MILLION BASE PAIRS

The midge can survive temperatures as low as -15°C. By burrowing a bit under the snow, where temperature is stable at a few degrees below zero, it can survive even when air temperatures get down to -40°C, which is not uncommon there

Not only can it survive subzero temperatures, it also requires it to survive! A study found that larvae exposed to even +10°C (50°F) died within a week

The midges can survive being frozen, dehydrated, and blasted with UV radiation. They are pretty darn resilient but then again, they’d have to be to live where they do!

Image © Richard E. Lee Jr.

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