Other Common Names: Caddisflies, sedges
Scientific Names: order Trichoptera

The caddis life-cycle is radically different from that of mayflies:

  1. First, caddis have an additional stage of development, changing from a larva to a pupa; the winged adult emerges from the pupa.
  2. A second difference between caddis and mayflies is that the adult caddis emerges so quickly from the pupa that it is seldom available to trout during a hatch. However, the adult will live several weeks, spending much time in bankside trees and grass. They often fall or are blown onto the water, where trout eat them. Therefore, while mayfly adults are mostly eaten by trout when they hatch, caddis adults are mostly eaten when they are not hatching.
  3. A third difference is the manner in which eggs are laid. Some caddis species drop their eggs into the water from above, where trout can't get them. But many others crawl or swim to the bottom, deposit their eggs, then return to the surface. Throughout the egg-laying process they are vulnerable to trout.
  4. Finally, caddis are long-lived (compared to mayflies), vary in color even within the same species, and have overlapping hatch seasons. Therefore, on any day during the caddis season, trout are used to seeing adult caddis in a range of sizes and colors. This is good news for fly anglers: it means precise imitation is seldom necessary. "Close" is usually good enough when playing horseshoes or when tying caddis patterns.

Caddis live in both lakes and rivers. River-dwelling caddis are a well-behaved and easily understood group. Lake-dwelling caddis, on the other hand, defy generalization. For example, the famous travelling sedge is usually from the genus Banksiola. But other species of caddis--from different families, even--exhibit running behavoir just like the genus Banksiola; anglers call them "travelling sedges" too. Fortunately, most of the differences between families and genera are of little importance to either anglers or trout.

For details on individual genera and fly fishing tactics, use the pull-down menu below. You can look up a genus by either its common names (each genus may have more than one common name) or its scientific name.


LARVA: Larva are worm-like. Cased larva will build its "shell" from tiny pebbles or plant debris and may pull its head inside the case when threatened or getting ready to pupate; cases may be rectangular, cylindrical, or dome shaped. Free-living caddis do not build a case.

PUPA: Two pairs of wings, not fully formed and swept along underside of abdomen. Long antennae. Legs not fused to body. Body usually encased in shroud. Body and shroud colors vary; body color may be different than either adult of larval forms.

ADULT: Two pairs of wings held over abdomen in triangular, "pup tent" shape. Fine hairs on edges of wings. Long antennae.