This is widespread and abundant spring-time sedge from running waters. It hatches on the open water. Huge swarms can be seen above the high and mid altitude rivers. Waterside bushes and bridges can be buried with grannoms.
Length of the wings can vary between 6 to 11 millimeters. The body is grayish with green or brown tone. Characteristically, the female has a pouch with green eggs on the abdomen, which will lay walking under water.