Adults are pale green with brown legs and grow to 12 millimetres (0.5 in). Males have feathery antennae while females' antennae are sleek. There is a dark brown band at the end of each abdominal segment. Adults of the sibling species C. muratensis and C. nudiventris cannot be distinguished from C. plumosus based on morphological characters.
The larvae are called bloodworms because some larva are bright red, but they can also be found in brown and almost black. When the larva pupate they will drift towards the surface, making them vulnerable to many types of fish. Other common predators include the common backswimmer (Notonecta glauca), common pondskater (Gerris lacustris), common toad (Bufo bufo), lesser water boatman (Corixa punctata), dragonflies, damselflies, great crested newt (Triturus cristatus), great diving beetle (Dytiscus marginalis), redstart (Phoenicurus phoenicurus), smooth newt (Triturus vulgaris), water scorpion (Nepa cinerea) and other midges such as Anatopynia plumipes.
During the spring and summer males will create mating swarms which people can find quite a nuisance even though adults do not bite, or feed. Females will lay egg masses in water where the egg mass will grow and sink to the bottom. The larva stay at the bottom in silken tubes. The larva feed on organic material such as organic debris and algae.
- Ryser H, Scholl A, Wülker W (1983). "Revision der Gattung Chironomus Meigen (Diptera) VII: C. muratensis n. sp. und C. nudiventris n. sp., Geschwisterarten aus der plusomus-Gruppe.". Revue Suisse de Zoologie 90 (2): 299–316.
- "Chironomus plumosus - Buzzer Midge — an Illustrated Guide". Retrieved February 10, 2009.
- "Non-biting midge - Chironomus plumosus". Natural England. Retrieved February 10, 2009.
- Evans, Arthur V. (2007). "Flies: Order Diptera". Field Guide to Insects and Spiders of North America. Sterling Publishing Co., Inc. p. 235. ISBN 978-1-4027-4153-1.