Netspinning caddisfly (Hydropsyche simulans). Class: Insecta. Larval caddisflies are extremely abundant at one study site (775,000 caddisfly larvae per pond), and appear to be resistant to the negative effects of ingesting tetrodotoxin. To many non-anglers, they look like little moths. It turned out that caddisfly larvae were the only predator that dared eat the eggs. They eat small aquatic vascular plants, nymphs, and larvae. Caddisflies are in abundance on the majority of moving waters, thus be sure to use these ones on a regular basis. Family: Brachycentridae, Humpless Casemakers. Their favorite algae is diatoms, which they scrape off of rocks. Size: 0.2-0.5 inch (6-12 mm). As larvae, these tiny creatures forage through the leaf litter and mosses of the woodland floor, feeding on decaying plant matter, slime molds and algae. But unlike moths, caddisflies spend most of their lives living in the water as larvae, which look like little worms. Caddisfly larvae represent an important ecological component of nutrient processing and energy flow in lakes and rivers and provide a food source for a variety of aquatic predators, such as trout and other fish (Resh and Rosenberg, 1984; Johansson, 1991; Wiggins, 1996a). Caddisfly larvae can take a year or two to change into adults. Family: Brachycentridae, humpless casemakers. Some of them, though, are predacious: they eat other animals. Most larvae live in these shelters, which can either be fixed or transportable, though a few species are free-swimming and only construct shelters when they’re ready to pupate. The caddisflies, or order Trichoptera, are a group of insects with aquatic larvae and terrestrial adults. However, even then identification to the species requires a microscope and identification keys, but fortunately, the latter are comparatively inexpensive. Adults have wings shaped like a tent, segmented bodies without tails, and antennae that give a moth-like appearance. Not only did they eat the eggs, but it was found that caddisfly larvae that were fed newt eggs actually grew larger than those that fed on pond muck alone. Caddisfly larvae live underwater, where they make cases by spinning together stones, sand, leaves and twigs with a silk they secrete from glands around the mouth. Once they become adults, caddisflies stop feeding to concentrate on breeding, then die after a few weeks. Habitat & Habits: Brachycentrid larvae live in streams and build cases which are either 4-sided and like a log-cabin or are cylindrical.Larvae creep around, often clinging to woody debris in the stream. There are approximately 14,500 described species, most of which can be divided into the suborders Integripalpia and Annulipalpia on the basis of the adult mouthparts. Most of the caddisflies are herbivorous--that is, they eat decaying plant tissue and algae. After hatching, larval newts retain substantial quantities of TTX and most are unpalatable to predatory dragonfly naiads. Much like the garter snake, it seems the caddisfly larvae had evolved a defense against tetrodotoxin. Identifying the caddis larva Whereas there are no easy characters to identify groups of caddis adults, several groups of caddis larvae are easy to recognise. They eat small aquatic vascular plants, nymphs, and larvae. The 3 gills are leaflike or paddlelike and positioned in a tripod configuration at the tip of the abdomen (unlike the gills of the related dragonflies, which are hidden within the tip of the abdomen). The “caseless” larvae These larvae make a silken net on top of rocks and feed on the algae and diatoms that are swept by the current into their nets. Caddisflies are perhaps the most underappreciated aquatic insect family. Damselfly larvae (nymphs) are aquatic, slender, usually drab insects, with 6 thin legs, large eyes, and small wing buds on the back of the thorax. Order: Trichoptera, the caddisflies. There are four stages of this prolific insect, and those videos below show imitations of the larva and pupa stages...two of my favorite stages to fish!