Making a Case for a Couple Trichoptera

Trichoptera (caddisfly) larva are amongst the most vital in the assessing of aquatic ecosystem health. They are usually the most sensitive to pesticides, and their vital role in the ecology of sports fish, such as trout, make them incredibly valuable to fishermen as well. They exhibit many different lifestyles and can be found in flowing streams, edges of lakes, and even stagnant wetland pools. Perhaps the easiest way of identifying them is by the cases that some of them build using silk and other materials, not unlike that of certain caterpillars (which they are closely related to), and their worm-like bodies with anal hooks at the end of their abdomen. To those new to identifying aquatic insects, they may simply look like worms, or even Dipterans (flies), but using some form of magnification, one would be able to see three legs on their thorax, which sets them apart from the legless Dipteran larva.

So far in my tank, I have two different families of Trichoptera: Leptoceridae and Hydropsychidae. These are two quite different groups of Trichoptera, and although I lack a dissecting scope (which I sorely miss at the moment) I believe I have a few identified down to genus.

Leptoceridae: Nectopsyche

Perhaps one of my favorite Trichoptera, these are commonly referred to as Long-Horned Case-Maker Caddisflies. They are typically found in cases made of fine grains with plant material attached to the outside. They also have extremely long back legs that typically have black on the joints. The first one I collected I could not stop taking pictures of, although none of them do it justice. I had to search elsewhere to find good enough pictures to show just how amazing these Trichoptera are.

B. The characteristically long antennae. C. One species without long antennae has a characteristic double line.

The genus Nectopsyche is omnivorous and have portable cases that allow them to roam looking for food. In fact, I believe these are the most mobile Trichoptera I have ever collected. Unfortunately, there is not much work done on this genus in North America, most of what I found concerned the Neotropical species that were recently discovered. They are quite common and there are at least 15 species found in North America.

Nectopsyche spp. with its case.

Hydropsychidae: Cheumatopsyche

Perhaps one of the largest families and one of the most common throughout North America. Like most Trichoptera, they use their silk to create cases, but instead of being portable, these cases are permanent retreats on the bottom of boulders. At the mouth of the cases, they spin nets to trap particles passed downstream by the current. When put out of these retreats, they will try to take one from another of the same species.

Again, not one of my pictures.

These are quite aggressive to conspecifics (same species). They are usually widely dispersed in streams unless there is a large amount of cobble for them to use to make retreats. During my research I've found this genus to be the most commonly used in assessment of streams due to their high sensitivity.

I'm hoping to go sampling either today or tomorrow, and will focus on finding species I do not already have.