Wingspan 10-12mm. This small fly which rests with its wings in a tentlike fashion and resembles a brown lacewing is actually a Spongefly from the family Sisyridae within the order of Neuroptera. Note the antennae are completely dark compared to other similar species of which there are three in Britain within the same genus Sisyra.
The larvae are entirely aquatic and feed within the tissue of freshwater sponges. This is the most common and widespread species encountered, and is seen in association with slow-moving or static water. The adults are seen May to October.
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August 2017, attracted to moth trap, rear garden, Staffordshire, England.