Caddis Caddis Order - Trichoptera Source of Name - "Trichos" meaning "hair" and "pteron" meaning "wing". "Caddis" meaning builders of nets or cases. There are approximately 10,000 species of them in the world and 300 in the western U.S.. This aquatic insect can vary in color even within the same species. Most have a one year life cycle but some species develop two generations or more each year. They go through complete metamorphosis unlike a mayfly, this means that they will go through four stages of development which are egg, larva. pupa, and adult. Most of their life is spent in the larva stage. You can identify a species of this insect easiest during this stage. They have no wing pads, very small antennas, short legs with a single claw on the end of each one, gills on it's abdomen, and no tail - instead they have a pair of anal hooks at the end of their abdomen. There are five distinct groups of caddis larva:The free living caddis, which does not have a shelter or case to live in.The saddle case caddis, which builds a dome shaped case that completely covers them, except for a very small opening on each end.The net spinning caddis, which builds a shelter and spins a web next to it to catch food.The purse case caddis, which build cases of silk and fine sand (also known as micro caddis).And finally the tube case caddis, which builds a portable case that allows them to move around and provide a retreat when disturbed.When the larval stage is complete the caddis will pupate. Pupation is a lot like hibernation to this insect, they stop eating and live in a cocoon much like a butterfly until they are ready to emerge to their adult stage. During pupation they enclose themselves in transparent shucks and are now called "pharate adults". A caddis pupa is very easily identified by its wing pad which are are half the length of its abdomen, its antennas which are long and laid back over its body, and a lack of anal hooks. This stage can take anywhere from two weeks to an entire winter. When the pupa is ready it chews out of its cocoon and swims very quickly to the surface where it splits its pupal shuck and the adult emerges. Soon after emergence the adult males form mating swarms to attract females and mating takes place on stream-side foliage. Once the females are fertilzed they head back to the water to either drop clusters of eggs on the waters surface or crawl under water to attach them directly to the substrate. The adult is identified by its four wings which are in a tent-like shape over its abdomen, antennas that are the length of its body, and the lack of a tail.
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