Large Dark Olive Mayfly vs Arctic Chironomid Midge

Side-by-side species comparison

Attribute Large Dark Olive Mayfly Arctic Chironomid Midge
Scientific Name Baetis rhodani Diamesa mendotae
Order Ephemeroptera Diptera
Family Baetidae Chironomidae
Size 6-10 mm 3-6 mm
Habitat Rivers & Streams Rivers & Streams
Diet Omnivores Detritivores
Regions Europe Arctic Canada, Alaska, Greenland, Scandinavia, alpine regions worldwide
Conservation Least Concern Least Concern

Large Dark Olive Mayfly

The most common European mayfly, emerging year-round in many rivers. It is a small olive-brown species that serves as a staple food for stream fish.

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Did You Know?

This mayfly can produce up to three generations per year, making it available as fish food in every season.

Arctic Chironomid Midge

A slender, non-biting midge with long legs and feathery antennae in males. Larvae are among the first invertebrates to colonize glacial meltwater streams. Adults can be active at temperatures just above freezing.

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Did You Know?

Diamesa midges can fly and mate at temperatures as low as minus 6 degrees Celsius, making them among the most cold-tolerant flying insects.