Pond educational resource pack

CORNWALL

Other insects

Found in the bottom mud, alder fly larvae are predators which are particularly fond of bloodworms, caddis fly larvae, mayfly nymphs and worms. Depending on size, these are swallowed whole or bitten into smaller pieces. The larva has a conspicuous row of gills along each side of its body. Adult alder flies are poor fliers, which hold their wings in a roof shape when resting. They are related to the lacewings.

Caddis flies are renowned for the cases which the larvae of most of their species build to protect and disguise themselves. Only their heads and legs protrude. Different species use different materials, including leaves, twigs, shells, sand, pebbles etc. Most of them crawl around on the mud and vegetation, taking both plant and animal food. Gills protrude from the sides of their bodies. Like alder flies, the adults are poor fliers whose wings are held roof-like when at rest. They look similar to moths but their wings are hairy.

Mayfly nymphs burrow, crawl or swim, feeding mainly on algae and decaying plant material. They are distinguished by their three "tails" and by the fringes of gills along the sides of their bodies. Adult mayflies are delicate, weak-flying insects which are well known for their spectacular mating swarms. After mating, a mayfly dies – sometimes the same day as it emerged.

Some moth species have larvae (caterpillars) which live under water. Those of the group known as china moths do so by constructing air-filled mobile homes out of fragments which they cut from leaves. Like all caterpillars they feed voraciously on plants, in this case water plants.