Order:
Adults: With or without wings. If wings present, forewings typically leathery or hard basally and translucent and flexible apically. Nymphs: With or without wing pads. Segmented legs present. Mandibles hidden within needle-like beak in adults and nymphs.
Family:
The mouthparts are slender, needle-like; the antennae are short and hidden from dorsal view; the body is parallel-sided and at least ΒΌ inch (5 mm) long; the front legs are slender; the middle and hind legs are fringed with swimming hairs; the hind legs are long and flattened, oar-like; swims upside down.