E. venosus is a relatively large sized larva. It is present in trout-habitats with clean, fast-flowing waters. It is an important mayfly for fly anglers in Europe.

The larvae (nymphs) prefer areas with rocky or stony bottoms. They are often found in riffle areas. They are flattened nymphs that live on the underside of rocks.. They are grazers that feed on periphyton (algae) and organic detritus on the stones.

The larvae emergence happens from April to July, with broods sometimes appearing until October.

In E.venosus the tarsus has only one dark band near the claw