Riffle Beetle vs Grey Longhorn

Side-by-side species comparison

Attribute Riffle Beetle Grey Longhorn
Scientific Name Elmis aenea Acanthocinus griseus
Order Coleoptera Coleoptera
Family Elmidae Cerambycidae
Size 1.5-2.5 mm 8-16 mm
Habitat Rivers & Streams Forests
Diet Detritivores Wood Feeders
Regions Europe Europe, Caucasus, Western Siberia
Conservation Least Concern Least Concern

Riffle Beetle

A tiny, dark beetle that spends its entire adult life underwater clinging to rocks in riffles. It breathes using a plastron, a permanent thin film of air.

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Did You Know?

Its plastron air film never needs replenishing, allowing it to remain permanently submerged.

Grey Longhorn

A small, cryptically colored longhorn beetle with grey pubescence and faint darker markings on the elytra. It inhabits conifer forests across Eurasia, breeding in dead branches still attached to trees. Adults are nocturnal.

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Did You Know?

Males guard females during oviposition by standing on top of them, preventing rival males from mating.