Western Encephalitis Mosquito vs Orthoclad Stream Midge

Side-by-side species comparison

Attribute Western Encephalitis Mosquito Orthoclad Stream Midge
Scientific Name Culex tarsalis Orthocladius oblidens
Order Diptera Diptera
Family Culicidae Chironomidae
Size 4-6 mm 3-5 mm
Habitat Wetlands Rivers & Streams
Diet Blood Feeders Detritivores
Regions Western North America, from Canada to Mexico Europe, North America
Conservation Least Concern Least Concern

Western Encephalitis Mosquito

A medium-sized mosquito with a distinctive white band on the proboscis and banded legs. It is the most important vector of Western equine encephalitis and St. Louis encephalitis in western North America. It breeds in a wide variety of sunlit and shaded water sources.

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Did You Know?

Its feeding behavior shifts seasonally from birds in spring to mammals in late summer, which drives encephalitis virus spillover to humans.

Orthoclad Stream Midge

A small non-biting midge typical of cold running water habitats. Larvae build silk tubes on stone surfaces in stream riffles.

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Did You Know?

Orthocladiinae midges are often the most species-rich insect group in pristine mountain streams.