Limnephilus genus
BioPix
Caddis flies are a large
group of insects
that live both in water and on land. There are over 1,100
species of caddis flies in the United States. Northern
Caddis Flies are a family
of caddis flies living throughout the country, and some of
them live in Northern Virginia. The pictures on this page
are all of the Limnephilus genus,
though they are of different species. It is difficult to
find pictures of particular species, especially because
there is so much we still don't know about caddis flies.
Most of the caddis flies in the Limnephilus genus
look a lot alike. Virtual Exhibit on
Canada's Biodiversity
BioPix
Caddis Flies spend most
of their lives in water, especially lakes, ponds, or
slow-moving streams. Adult
Northern Caddis Flies live out of the water and have four
wings which are brown with patterns on the them. They are
not strong fliers and flutter a lot like moths. Caddis flies
are not real flies; they have long antennae
and legs. Adults are usually active at night, and they
rarely go far from the water where they were
born. After mating, female
caddis flies lay their eggs in the water. Almost as soon as
a larva
hatches from its egg, it starts building a case. To do this,
the larva gathers bits of twigs, leaves, grass, sand,
gravel, seeds,
bark,
mollusk
shells, and other items it finds on the bottom in the water,
and it glues them together with a sticky substance from its
mouth. The caddis case will be the larva's protection for
most of its life. Copyright, Edyta
Serafin Dr. Donna J.
Giberson The caddis fly larva can
stick its head and legs out of its case, which looks like a
long tube. When in danger, it can tuck itself inside. The
larva can also crawl around, carrying its case with it, much
like a hermit crab. Inside the case, the larva has small
hooks at the end of its body to help hold onto it. As the
larva grows, it can add onto its case. Larvae feed during the
day. They are grazers and eat whatever they can find on the
bottom, including algae,
fungi,
detritus,
and very small invertebrates. When the larvae are full
grown (late Spring or early Summer), they are ready to
pupate
(go into a resting stage). Each larva attaches its case to
the bottom, or to a rock or plant. Then it plugs up the hole
of its case. The caddis fly stays a pupa for two weeks. At
the end of two weeks, the pupa is able to push its way out
of its case and finds its way to the surface. The pupa then
changes to an adult Northern Caddis Fly and flies
away. Biologische
Untersuchung
