Category Archives: Macroinvertebrates

Like an OK Cupid profile, but for water bugs.

Greenway Network monitors every place a road crosses Dardenne Creek

photos by Bob Virag, Stream Team volunteer
words by Larry Ruff, Greenway Network 

Dardenne Creek is 27 miles long.  It originates in Warren County, flows northwest through St. Charles County and empties into the Mississippi River directly north of St. Peters.  It is a pretty creek in its headwaters–Ozarkian in nature.

ST 463 Dardenne Day 10-12-14-A little rain doesn't stop us!
Monica Hull, Larry Ruff, and Matt Hull kick around looking for macroinvertebrates on October 12, 2014. A little rain doesn’t stop us!

In the ’20s and ’30s, farmers channelized the creek in the flatter regions of the county. Those farms have become hundreds of subdivision neighborhoods. It crosses I-70 at St. Peters and runs through he Mississippi River floodplain. Every where a road crosses the creek, Greenway Network tries to monitor that site.

Lindenwood Univ student volunteers
Lindenwood University students enjoying lunch provided by Greenway Network after the stream monitoring.
Gail Johnston ST 2819 & Larry Ruff ST 463
Gail Johnston is a Biology instructor at Lindenwood University (ST 2819) in St. Charles and always brings students to Dardenne Day.

We’ve been doing Dardenne Day for at least 14 years. Monitoring takes place in the Spring and the Fall. This year, Dardenne Day was part of 25 Days of Stream Team.

In the Spring: 19 sites on the creek were monitored by 29 volunteers, 9 different Stream Teams.

In the Fall: 16 sites monitored by 10 volunteers, 5 Stream Teams.

Curious about how all these site visits turned out? Download results here and see for yourself! Macro ratings ranged from 0 to 25, pH hovered around 8.2, and they even logged e. coli numbers. Very interesting.

If you want to get involved with Dardenne Day or any of the other great events put on all year by Greenway Network, visit their website.

Snail Case Maker Caddisfly (Helicopsychidae)
Snail Case Maker Caddisfly (Helicopsychidae)


Everything you need to know about the Midwest’s fresh water mussels

Once again, here’s a warm welcome to the MObugs blog genius Shelly Cox . She’s been kind enough to share some of her writing on aquatic insects with the whole Stream Team community. Go check out her blog, which features really beautiful, exclusive photos, and a lot of  insider knowledge on the whole bug community.

This past 4th of July we spent an evening at the farm. We enjoyed a cookout, great friends and fireworks. The kids swam in the pond and soon discovered mussels underfoot. They grabbed up hundreds of them and placed them in a 5 gallon bucket. They were having fun finding them. I decided I wanted to try and cook some. So I kept 20 or so, and threw the rest back into the pond. I brought the mussels home and soaked them in water for a few hours, and then sauteed them in butter, onion and some seasoning. They were not near as good as I had hoped for. They maintained a muddy taste from the muddy bottom of the pond. I suppose if I had soaked them for a longer period to time it could have helped. If anyone has prepared these with success, please let me in on the secret.

As you can see the kids were having fun diving for mussels in our pond. What a great way to spend a hot summer day!

There are hundreds of fresh water mussels in the World, and nearly 300 of them live in North America. In fact North America is home to the largest variety of mussels compared to anywhere else in the World. Many are in threat of becoming endangered, in fact the estimate is as high as 3/4 of the known species may be in peril. As many as 35 species have already gone extinct. The Midwestern portion of the United States contains the highest concentration of species, Missouri alone is home to some 65 species. Native Americans utilized mussels as an important part of their diet. Not only were they a valuable food source for tribes throughout the Midwest, but they also held value in other ways. The shells were used for tempering pottery and tools, they also made jewelry, and utensils. In the late 1800’s “white man” recognized the potential value of the shells in the fashion industry. The button industry reached a boon during this time in history and many mussels were collected for the “mother-of-pearl” and sold to the button factories. The epicenter for the button industry was right in the good old Midwest. Continue reading Everything you need to know about the Midwest’s fresh water mussels

What’s the Water Scorpion’s favorite drink? Insect Slurpee.

We are as happy as a heron in a fish pond to welcome the MObugs blog’s own Shelly Cox to our anniversary site. She is kind enough to share some of her writing on aquatic insects with YOU, dear readers. Go check out her blog, which is chock full of all kinds of nutty bugs, all native to Missouri!

This crazy looking stick-like insect is NOT a Stick Insect. It is in fact a Water Scorpion in the family Nepidae. They are in the same order as other true bugs, Hemiptera. In spite of their common name of “scorpion” they look nothing like a typical terrestrail scorpion that we’ve all seen in pictures or on nature programming.

Water Scorpion
photo by Shelly Cox, of the MObugs blog.

They do not have a stinging tail or venom that they inject with a painful sting. They are very long and thin just as this picture shows. Their front two front legs are used to grab insect prey and pull it back into their mouth to feed. They will eat tadpoles, tiny fish like minnows or offspring of other fish (in captivity they do well on young guppies), they will also feed on other aquatic insects. Their mouth is much like another group of insects within this order called the assassin bugs. It is a beak-like structure that pierces the outer skeleton of their prey, then they inject them with an enzyme which sedates their prey as well as liquefying the insides of the unfortunate victim. The water scorpion can then slurp up the insides like an insect slurpee.

The long “tails” that protrude from the backside of the scorpion are actually breathing tubes. They typically float on debris or plants near the waters surface where they will extend their breathing tubes out of the water. They can swim, but seldom do unless disturbed.  They will overwinter as adults and lay eggs the following spring. The female will lay her eggs in vegetation near the shore line or on the surface of the water. In about 2 to 4 weeks the eggs hatch and the young begin feeding on tiny insect prey. It takes them about 2 months to reach maturity. It is not uncommon to see one of these crazy looking insect reach lengths up to 5 or 6 inches. These crazy bugs possess wings and will fly.

photo by Shelly Cox, of the MObugs blog
photo by Shelly Cox, of the MObugs blog

The one pictured here was captured by a little girl during a field trip to my office. We were hosting a local preschool for a field trip to the pond. We divided the group into two separate groups. One half of the group fished, while the other half mucked around in the pond for aquatic insects. Then we switched the groups. One of the girls in the first group pulled her net into shore and screamed that she caught a water spider. I went to investigate and discovered that she had caught this water scorpion. It was only the second one I’ve ever seen and certainly the biggest at approximately 3 1/2 inches in length. I made a big deal out of her capture and told her what a special insect she caught. She was thrilled. After the group left I kept the scorpion and placed it in a tank. I’ve been feeding it freeze dried crickets. We will keep it for a few weeks and use if for programs before releasing it back to the pond it came out of.

Visiting the pond, lake, stream or other water source and exploring for a few hours with something as simple as a net and a shallow dish can yield all sorts of interesting insects to learn about. Get out and discover what is hiding below the surface.

Caddisfly larvae: hippie homesteaders of the streams

Let’s review your friends and acquaintances. They mostly live in houses, take regular showers, enjoy the occasional dinner out, and go with the societal flow, right? 

But you know that guy…

That guy . . .

The one who constructed a home out of logs he cut himself and Styrofoam chunks he pulled off a riverbank? Who eats only what’s in season and criticizes places with too much pollution? And that same person, when they’re not surveying the back 40, probably occupies himself with crafts like spinning his own thread or making jewelry . . . got that image in mind?

See, if you lived in a stream, “that guy” would be a caddisfly larva.

In fact, it’s kind of hard to tell the two apart . . .caddisfly infographic


Your hair is everywhere: First off, the caddisfly order Trichoptera is Greek for ‘hairy wing,’ and you knowww how the treehugger type loves being hairy. The Caddis part means cotton or silk; in Elizabethan era, “caddice men” (vendors of ribbons, braids, etc.) pinned their goods on their coats.

Casemaker, homesteader, potato potahto: When these creatures spin a silk case or cocoon around themselves, they also tie on nearby debris — sand, rock, twigs, leaf pieces, shells. The cases are functional, allowing water in and out over the larval gills. They’re sturdy, sometimes weighing the creatures down in the current.

In a couple of years, the caddisflies’ descendants will point to those little cases trembling in the riffle and say, “My grandfather built this house with his own six hands, with material right from this stream!” Everyone will be impressed.

Equal rights for every invertebrate! There’s a sad side to this industrious behavior. As often happens in global markets, so too are humans are exploiting caddisflies for commercial purposes. In this case, to make jewelry at a high markup. Artists just plop the little larvae in an aquarium filled with gold flakes, pearls, and precious stones, and the caddisflies do the rest. We have to admit, the results are pretty stunning:


Can I have the reverse osmosis water, please?: Another value of the caddisflies is their exacting taste in water. According to this Biomonitoring Macroinvertebrates site, “They breathe dissolved oxygen by diffusion across their soft tissues, and they have a limited ability to cope with low dissolved oxygen by wiggling their bodies within their cases. However, they lack the ability to breathe atmospheric oxygen that some other more tolerant insects have.”

So if you find a caddisfly larva in your stream, congratulations! You have a stream worthy of an eco-snob’s standards. I know I was excited when I spotted this little guy at Clifty Creek Conservation Area in Dixon in February:

Take it easy, man: Finally, it’s just easy to admire the caddisfly larva’s mellow take on life. When it comes to building houses, they work with what they’ve got. They eat what food’s available to them and are willing to change their munching style to do so. They can live in ponds, lakes, rivers, streams, whatever’s fresh. And they are willing and accepting, for goodness sake, to completely metamorphose into an entirely new body at the simple change of a season. Enlightened? Check. Good head on their shoulders? Check. Ain’t nothing wrong with being a hippie, Mr. Caddisfly. You keep on doin’ you.

More information

The Beginner’s Guide to Caddis

Bug Guide on Trichoptera’s 1,350+ species

 P.S. – Huge thanks to Mark Haim for letting us use his image in this graphic. And thanks to the caddisfly, too, wherever you are.

What dragonfly nymphs know about teenage angst

Photo by Flickr user Steve Begin

You know, just when you thought you knew a dragonfly, they surprise the heck out of you by having babies. Then those babies morph into progressively larger, weirder nymphs and wreak progressively more havoc on larvae living in streams. It’s a little unsettling. But that’s life on the playground, kids, and that’s just how it goes. That’s your moral of this story today.

But first, a little taxonomy: Dragonflies belong to the order Odonata, which comes from a Greek word meaning “toothed,” and refers to the mandibles of these carnivorous insects. The infraorder name Anisoptera comes from the Greek anisos, which means ‘unequal’ and pteron, meaning ‘wing.’ This won’t help you identify them in the nymph stage, however, because they all look like freaky, wingless monsters.

Look at this cute little baby dragonfly. Don't you just want to cuddle it? What? No? Well neither does its mother. Maybe that's why it eats other insects.
Look at this cute little baby dragonfly. Don’t you just want to cuddle it? What? No? Well neither did its mother. Maybe that’s why it eats other insects. Photo by Cyndy Sims Parr.

Where they live: Ponds and slow-flowing rivers near aquatic vegetation or in calmer areas of streams.

You can identify them by: Sheer weirdness. And they don’t have tails like damselfly, mayfly or stonefly nymphs. Probably because their butts are busy doing other things.

If water bugs had yearbooks, dragonflies would be voted: “Most Likely to Commit a Violent Crime.”

And would be runner-up for: “Most Likely to Write a Coming of Age Novel.” Seriously, these naiads take forever—like up to 95% of their life cycle—just molting into progressively bigger forms. When they hatch from an egg, they look stout, dull-colored, and frumpy. No resplendent wings or colorful patterns here. About the only thing they share with their parents is an insatiable thirst for other insects.

Which brings us to: The part where we scare the pants off of you.

Slow-mo dragonfly nymph labium (lower lip) in action. The actual strike only takes 10 milliseconds. From Bulanbeck.
Slow-mo dragonfly nymph labium (lower lip) in action. The actual strike takes 10 milliseconds. From Bulanbeck.

Aaagh, look at that! Oh, it’s too horrible! Oh, but you can’t look away! Dragonfly naiads have gigantic hooked labium, or extendable lower lips, that snatch victims in milliseconds. Once again, the rectum aids in this process.  (It also helps with breathing. And moving. Dragonflies are probably the butt of a lot of jokes.)

What they eat: Larvae of bugs, including other dragonflies and mosquitoes. And maybe the souls of litterbugs.

Which is good for us because: Nobody likes mosquitoes. Or litterbugs.

For more information, visit the Tree of Life project entry on Odonata and University of Michigan’s Animal Diversity Web.

Things to know before you date a Water Penny Beetle Larva

Photo from the Marietta College Department of Biology and Envrironmental Science

Water Penny Beetles are in a family called Psephenidae, under the genus Psephenus, which comes either from psephenos (ψεφηνος), meaning ‘dark, obscure’, or psephos (ψηφος), ‘a small round worn stone, pebble.’ Our money’s on the pebble, because that’s what the larvae look like. Or a penny. A tiny penny for dolls.

In case you’re thinking of taking a water penny beetle out on the town, here’s what you should know:

Favorite food: Microscopic organisms and algae salad.

Where they hang out: Swift currents in streams worldwide.

Personality: Kind of fussy. Sensitive to light, inorganic sediment, and too much algae. They cling to grassy clumps and the underside of rocks in the daytime. At night, they eat on top of the rocks: think, “outdoor balcony, after-hours in a posh restaurant.” The adults don’t live long, so after metamorphosis they mostly let the good times roll and mate a lot: scientists have observed females laying 400-600 eggs in a single patch. They really love oxygen and can’t tolerate pollution.

Which means: Water penny larvae have good taste and live in high-quality streams.

Which is too bad for them because: They make yummy treats for fish living in those high-dollar neighborhoods.

But good for us because: Their presence tells us when a stream is healthy. And they make free fish food.


For more information, visit UW-Milwaukee: Field Station Bug of the Week, the Tree of Life Web project entry on Psephenidae and the 1971 classic, “Ecology of the Water Penny Beetle (Psephenus Herricki)” by Chad M. Murvosh.