Caddisflies
In the Order of Trichoptera the caddisfly, of which there are approximately 7000 species, starts life in freshwater habitats and then emerge as an adult.
The name Trichoptera, derived from the Greek words “trichos” meaning hair and “ptera” meaning wings, refers to the long, silky hairs that cover most of the body and wings.
Caddisflies are moth-like insects with two pairs of hairy wings that are folded roof-like over the abdomen at rest. Antennae are long and many jointed with a large basal segment. Large compound eyes are present. [efn_note] Encyclopedia Britannica [/efn_note]
Life cycle
Eggs numbering around 800 at a time are laid in jelly that swells on contact with water. After a few days the larvae hatch. Depending on the species of caddisfly they may be herbivorous, carnivorous, or a bit of both (omnivorous).
In this larval stage the young caddisfly will protect itself in many different ways depending on the species. Some will spin protective silky webs around themselves. Some will use that silk to make a web to catch food and some will use it to attach debris to themselves to form a protective layer and camouflage from potential predators (see attached video).
The larvae are important to the aquatic community by controlling plant growth and animal and plant waste. The adult caddisflies are unable to eat solids so imbibe nectar from plants instead.
Parasitic wasps are known to seek it’s host underwater and lay eggs inside the protective case of the caddisfly. The egg hatches and the larval wasp devours the caddisfly larvae.
When the adults emerge, they behave much like moths, they are strongly attracted to light and can be found swarming around objects on the river banks or shore line.
Hopefully you get to see some of these amazing insets when you go pond dipping or moth trapping.
Tom