The larvae of Kempynus lacewings are unlikely to be mistaken for any other insects. They have long tusk-like mouthparts and long antennae projecting well in front of the head. The legs may be pale but otherwise the body is darkly pigmented, with a scattering of long black hairs.
Kempynus larvae are usually found along stream margins, including the splash zones of rapids and waterfalls.
They are thought to be predators, preying on other stream insects such as chironomid larvae.
Kempynus larvae are not truly aquatic and may not be good indicators of water quality. They have a hard bottom tolerance value of 5 (no value has been assigned for soft bottom sites).