We're blessed, here in northeastern Iowa -- blessed to have places where clear cold water comes out of the ground, in quantities large enough to attract and delight us.
In Decorah, if you turn from College Drive onto Ice Cave Road, and head toward one of our most popular local waterways -- Dunning's Spring -- you'll first come upon a much more modest spring, burbling out of the forested hillside on the north side of the road. Here it is on March 29:
I might have missed it, driving toward Dunning's Spring that day, if not for all its greenery, which seemed so out of place compared to the tans, browns, and grays surrounding it. Curious what all that green was, I stopped to take a look.
The new growth, I found, consisted mostly of watercress, reed canary grass, and jewelweed. Watercress is a recent introduction to North America (1), as are many populations of reed canary grass (2); I was less than thrilled to discover these plants in the mix (I guess I was hoping for a pristine wetland full of rare and conservative native species). But hey, jewelweed is native, and it sure was neat to see hundreds of its seedlings poking up bravely out of the muck, baring their cotyledons to the world.
Why now, jewelweed? Nowhere else was I encountering jewelweed sprouts so early. It seemed the answer lay in the site's unique abundance of both sunlight and flowing water. The slope here was steep enough that even the spring's relatively paltry flow moved too quickly for ice to encrust it; and the slope's southerly aspect meant it was pummeled daily with lots of direct sunlight.
Imagining that there might be some interesting arthropods here -- but not wanting to scrape up the slope by scrambling over it -- I hatched a plan to return tomorrow with a special tool in hand. The idea for a "slope stool" had been kicking around in my head for a few years, and now seemed like as good a time as any to actually make one. So, back at home the next morning, I scrounged up some scrap wood and threw something together.
Here it is that afternoon, set up on site:
Armed with my camera and "bug lens," I took a seat! It felt good to be sitting comfortably at the same level as the trickling water, wet ground, and pint-sized jewelweed forest I wanted to investigate. I leaned to my right and let the microcosm draw me in.
---
An initial surprise was the texture and quality of the substrate. Earlier I described it as "muck", and there was plenty of that -- but among and atop the muck was a profusion of little rocky bits. If you were to run your hand gently along the ground, under the thin film of water dribbling down the slope, these rocky bits are primarily what you would feel -- coarse, gritty, even sharp. It seemed likely they were calcareous, consisting of calcium carbonate (CaCO3) that had precipitated out of the flowing water over time. (A similar process results in subterranean features such as stalactites and stalagmites.) Lynch and Weckwerth (2017) use the term "limestone cobbles" to refer to the calcareous stuff they encountered in forested seeps in Winneshiek County (3) -- and I think that term is a fitting description in this case too.
Interestingly, some of these cobbles took the form of little tubes. Rather than being the products of slow deposition, these were actually the cases of caddisfly larvae, who had fashioned them from tiny pebbles, rock fragments, and other debris. Most of the cases appeared to be abandoned; these former larval shelters had simply accumulated on the slope over time, the surprisingly durable leftovers from caddisfly generations past.
When I looked into the slope's clear water, at a place where the water gathered and swirled for a moment before tumbling further downhill -- a shallow pool no larger than a soup bowl -- I spotted a few live caddisfly larvae in their cases, alternately resting, feeding, and moving about.
(Here's a video showing one of the caddisfly larvae making its way across the limey substrate.)
And the longer I watched the rippling puddles and miniature waterfalls on this sun-soaked slope, the more life I saw.
This small dark fly with a white face seemed to prefer walking rather than flying. For a long time it played hide-and-seek with my camera and me, dodging behind bits of vegetation or scurrying into shadowy cobble-craters just as the shutter was about to click. It most likely spent its youth as an aquatic larva here on this slope or in a similar place nearby, hunting and catching other arthropods for food. Croatian researcher Marija Ivković and her colleagues write, "Larvae and adults of Clinocerinae and Hemerodromiinae (Diptera: Empididae) are predators and therefore important as secondary consumers in stream food webs. Likely, they mainly feed on Simuliidae [black fly] larvae....and on Chironomidae [midge] larvae and adults...Some dance fly larvae have also been found in cases of caddis larvae, feeding on the pupae..." (4)
Certainly there was no shortage of caddisfly larvae in this hillside spring. I didn't run into any Chironomidae larvae in the spring that day, but I did find larvae from another group of flies commonly referred to as "midges" -- the meniscus midges, family Dixidae (dik-sid-ee).
It was fun to watch these beasts squirm their way across the wet substrate, using a peculiar twisting and writhing motion. Check out this video to see what I saw. The individual above didn't move much for some reason, which enabled me to capture a picture or two of the intricate, feathery appendages (gills?) on its rear end, held right at the water's surface.
I also came across a few tiny black bugs scampering this way and that. One of them I captured and placed in a bowl of water at home, where it skated around quite capably on the water's surface. This was a "smaller" water strider (family Veliidae), cousin to the much larger animals of the same name that are so familiar to many of us.
It was a very cooperative subject.
And what an interesting pattern on its back!
If you notice a passing resemblance to, say, the boxelder bugs so abundant in our homes over the winter, it's because they're related. Water striders and boxelder bugs alike belong to the broad group of insects known as the "true bugs." If you were to flip a boxelder bug onto its back (try it with a dead one) and examine its underside, you'd see a long straight rod running from its head down along the middle of its "belly." The bug extends this tubelike appendage away from its body in order to feed. Such feeding tubes, modified for various piercing and sucking habits, are common to many (all?) of the true bugs, and smaller water striders are no exception. Enjoying a few moments of calm amid its adventure in the bowl of water, my strider took time to groom its lancelike mouthparts.
Back at the spring -- as if all the previous critters weren't enough -- I was fortunate to encounter yet another charismatic arthropod: a species of soldier fly (family Stratiomyidae), in larval form.
Since I think these guys are way cool, I'm going all out with the photos. Here are my best attempts at a head shot of a live and active larva.
If you look closely, you can see the animal's eyes and antennae (yes, larval insects have antennae too!).
To be honest, observing them firsthand, I found these creatures to be a bit dopey -- but in a totally charming sort of way. And their feeding apparatus! It takes up much of the front of the head and quivers or palpitates rapidly as the larva moves about in search of food. Rudolf Rozkošný (1983) writes, "the mandibular-maxillary complexes [of stratiomyid larvae] are complicated structures with many setae, brushes, teeth or rows of projections in the molar area" (5). More easily than reading about them, though, you can get a sense for these larvae's crazy chompers by watching them in action -- here or here, for instance. (My bug videos aren't exactly studio quality, but I do hope you give them an chance when you can! Bugs are so much more interesting in motion!)
What exactly these larvae are collecting with all that fancy mouthwork, I'm not sure. However, algae are known to be the food of choice for soldier fly larvae that live on rocks covered in a thin film of water (6). Does the hillside spring along Ice Cave Rd qualify as that sort of hygropetric habitat? Another question I'm afraid I can't answer today.
But that's okay. Uncertainties and mysteries surround us in the study of life, and as collaborator MJ Hatfield likes to remind me, it's the mystery of it all that keeps us coming back. For example: How is it possible that the Universe could create an animal as delightfully ferocious as the one I'm about to show you?
This will be the final invertebrate from the hillside spring that I'll share with you on this post, and I do believe I've saved the best for last.
---
It's WEIRD!
It might MAKE YOU SCREAM!
It's...
...a predatory crane fly larva!
Oh my GOSH these things are cool.
Allow me to explain...
As I wrapped up my first visit to the hillside spring, I decided to bring a bit of it home with me. Mainly I wanted to rear the soldier fly larvae to adulthood, but I also figured there was probably some other interesting stuff hiding amid all the waterlogged muck and calcareous grit. So, I scooped up a few handfuls of the substrate and plopped it in a jar. Back at home I transferred this messy stuff to a shallow container. A few jewelweed sprouts survived the trip, and I "replanted" them.
If you look at the base of the twin sprouts near the top of the image above, can you see the wormy thing in the muck? It's a bit darker than its surroundings, and has some pinkish color to it.
I was pretty excited when I saw this; even though I had no idea what it was, it looked very interesting. I gingerly picked it out of the muck and dropped it into a bowl of water. What follows is the best shot I could get of the creature in the bowl, which writhed about as if unhappy to be plunked into such unfamiliar environs (imagine that!).
I posted this picture to the "ID Request" section of Bugguide.net, and within 24 hours a fellow contributor had identified the "wormy thing" -- to genus. (Bugguide is truly an impressive resource!) The animal was a species of Pedicia, one of the so-called "hairy-eyed" crane flies. This astounded me: I had no idea there were any fly larvae with such well-developed, pincer-like mouthparts. It seemed clear this was a predator; indeed, Bugguide's information page for Pedicia indicates that "larvae are strictly aquatic and predaceous, a good bioindicator of clean aquatic habitat" (7). What a beast!
In my Internet search for more information, I came across Jason Neuswanger's eye-popping photographs of a Pedicia larva. Besides greatly stoking my newfound enthusiasm for these flies, Jason's work really made me want to try for better photos of the larva I'd found. I never got around to it...but fortunately, when I returned to the spring a few weeks later and collected more substrate, a Pedicia larva turned up in the sample! It seemed like the perfect opportunity -- so I rigged up a teeny little aquarium and busted out my camera.
The first four Pedicia images above came out of that photo shoot; so did these:
Incredibly, the larva was able to completely retract its mouthparts into its front end:
And how about all those appendages on the rear end?
What a world.
---
Here's a photo of the hillside spring on April 24, roughly a month after I paid my first visit.
You might notice it looks less green than it did at the end of March! How did that happen?
Well, first, in early April we had two or three nights in a row with lows in the teens. Most of the jewelweed sprouts -- out in the open as they were -- didn't fare so well:
However, by some quirk of terrain -- or perhaps because they had sprouted amid last year's sprawling dead leaves of reed canary grass, and were thus slightly more sheltered -- some of these tough little seedlings survived.
But that wasn't all our wintry April had in store for the life on this hillside spring. Heavy wet snow descended upon the Decorah area in mid-April, and one afternoon, with a thick covering of white smothering most of the hillside, I visited the spring again.
I was amazed by what I saw:
Birds! Everywhere!
Video of the woodcocks feeding at the spring (they strut and teeter!)
These early migrant birds had flocked to the spring because, so soon after the snowfall, it offered them one of the only areas of open ground they could find -- and, as a living landscape even at this difficult time, the saturated muck abounded in easily accessible seeds and insects. (Not to mention fresh water to drink!) It wasn't so great to know that scores of soldier fly and Pedicia larvae were likely getting gobbled up -- but I was really happy for the birds, that they could find such sustenance here.
And the jewelweed sprouts? Well, by the time I revisited their home on April 24, most of them had perished. But a healthy fraction had persisted -- despite the worst that early spring could hurl upon them. They had narrowly dodged getting frozen to death, smothered by snow, and trampeled by a horde of hungry and desperate birds. And now it was sunny and warm on the hillside spring; and it was time to continue -- time to stretch proudly and fully upward, into the season of life.
---
NOTES
Thank you to my fellow contributors at Bugguide.net for furnishing identifications of the animals mentioned in this post.
1. Runkel, S.T. and D.M. Roosa. 2010. Wildflowers and other plants of Iowa wetlands. University of Iowa Press: Iowa City. Link
2. Reed canary grass webpage at ISU EEOB's Grasses of Iowa project; see also this Iowa DNR factsheet
3. Lynch, E.A. and A.B. Weckwerth. 2017. Herbaceous vascular flora of forested seep wetlands in Winneshiek County, Iowa, USA. Jour. Iowa Acad. Sci. 124(1-4): 1-10.
4. Page 43 in Ivković, M., Stanković, V.M., and Z. Mihaljević. 2012. Emergence patterns and microhabitat preference of aquatic dance flies (Empididae; Clinocerinae and Hemerodromiinae) on a longitudinal gradient of barrage lake system. Limnologica 42(1): 43-49.
5. Page 214 in R. Rozkošný. 1983. A biosystematic study of the European Stratiomyidae (Diptera): volume 2. Springer Science & Business Media: 431 pp.
6. Ibid., p. 95
7. https://bugguide.net/node/view/14194
In Decorah, if you turn from College Drive onto Ice Cave Road, and head toward one of our most popular local waterways -- Dunning's Spring -- you'll first come upon a much more modest spring, burbling out of the forested hillside on the north side of the road. Here it is on March 29:
 |
| Spring on wooded slope along Ice Cave Rd, Decorah, 29 March 2018 |
I might have missed it, driving toward Dunning's Spring that day, if not for all its greenery, which seemed so out of place compared to the tans, browns, and grays surrounding it. Curious what all that green was, I stopped to take a look.
The new growth, I found, consisted mostly of watercress, reed canary grass, and jewelweed. Watercress is a recent introduction to North America (1), as are many populations of reed canary grass (2); I was less than thrilled to discover these plants in the mix (I guess I was hoping for a pristine wetland full of rare and conservative native species). But hey, jewelweed is native, and it sure was neat to see hundreds of its seedlings poking up bravely out of the muck, baring their cotyledons to the world.
Why now, jewelweed? Nowhere else was I encountering jewelweed sprouts so early. It seemed the answer lay in the site's unique abundance of both sunlight and flowing water. The slope here was steep enough that even the spring's relatively paltry flow moved too quickly for ice to encrust it; and the slope's southerly aspect meant it was pummeled daily with lots of direct sunlight.
Imagining that there might be some interesting arthropods here -- but not wanting to scrape up the slope by scrambling over it -- I hatched a plan to return tomorrow with a special tool in hand. The idea for a "slope stool" had been kicking around in my head for a few years, and now seemed like as good a time as any to actually make one. So, back at home the next morning, I scrounged up some scrap wood and threw something together.
Here it is that afternoon, set up on site:
Armed with my camera and "bug lens," I took a seat! It felt good to be sitting comfortably at the same level as the trickling water, wet ground, and pint-sized jewelweed forest I wanted to investigate. I leaned to my right and let the microcosm draw me in.
---
An initial surprise was the texture and quality of the substrate. Earlier I described it as "muck", and there was plenty of that -- but among and atop the muck was a profusion of little rocky bits. If you were to run your hand gently along the ground, under the thin film of water dribbling down the slope, these rocky bits are primarily what you would feel -- coarse, gritty, even sharp. It seemed likely they were calcareous, consisting of calcium carbonate (CaCO3) that had precipitated out of the flowing water over time. (A similar process results in subterranean features such as stalactites and stalagmites.) Lynch and Weckwerth (2017) use the term "limestone cobbles" to refer to the calcareous stuff they encountered in forested seeps in Winneshiek County (3) -- and I think that term is a fitting description in this case too.
 |
| Cobbles formed by mineral deposition on a slope along Ice Cave Rd, Decorah, 30 March 2018 |
Interestingly, some of these cobbles took the form of little tubes. Rather than being the products of slow deposition, these were actually the cases of caddisfly larvae, who had fashioned them from tiny pebbles, rock fragments, and other debris. Most of the cases appeared to be abandoned; these former larval shelters had simply accumulated on the slope over time, the surprisingly durable leftovers from caddisfly generations past.
 |
| Tube-shelters built by caddisfly larvae |
When I looked into the slope's clear water, at a place where the water gathered and swirled for a moment before tumbling further downhill -- a shallow pool no larger than a soup bowl -- I spotted a few live caddisfly larvae in their cases, alternately resting, feeding, and moving about.
 |
| Inhabited case of a caddisfly larva, with the larva (not visible) resting inside |
(Here's a video showing one of the caddisfly larvae making its way across the limey substrate.)
And the longer I watched the rippling puddles and miniature waterfalls on this sun-soaked slope, the more life I saw.
 |
| Dance fly (subfamily Clinocerinae) |
This small dark fly with a white face seemed to prefer walking rather than flying. For a long time it played hide-and-seek with my camera and me, dodging behind bits of vegetation or scurrying into shadowy cobble-craters just as the shutter was about to click. It most likely spent its youth as an aquatic larva here on this slope or in a similar place nearby, hunting and catching other arthropods for food. Croatian researcher Marija Ivković and her colleagues write, "Larvae and adults of Clinocerinae and Hemerodromiinae (Diptera: Empididae) are predators and therefore important as secondary consumers in stream food webs. Likely, they mainly feed on Simuliidae [black fly] larvae....and on Chironomidae [midge] larvae and adults...Some dance fly larvae have also been found in cases of caddis larvae, feeding on the pupae..." (4)
Certainly there was no shortage of caddisfly larvae in this hillside spring. I didn't run into any Chironomidae larvae in the spring that day, but I did find larvae from another group of flies commonly referred to as "midges" -- the meniscus midges, family Dixidae (dik-sid-ee).
It was fun to watch these beasts squirm their way across the wet substrate, using a peculiar twisting and writhing motion. Check out this video to see what I saw. The individual above didn't move much for some reason, which enabled me to capture a picture or two of the intricate, feathery appendages (gills?) on its rear end, held right at the water's surface.
I also came across a few tiny black bugs scampering this way and that. One of them I captured and placed in a bowl of water at home, where it skated around quite capably on the water's surface. This was a "smaller" water strider (family Veliidae), cousin to the much larger animals of the same name that are so familiar to many of us.
It was a very cooperative subject.
And what an interesting pattern on its back!
If you notice a passing resemblance to, say, the boxelder bugs so abundant in our homes over the winter, it's because they're related. Water striders and boxelder bugs alike belong to the broad group of insects known as the "true bugs." If you were to flip a boxelder bug onto its back (try it with a dead one) and examine its underside, you'd see a long straight rod running from its head down along the middle of its "belly." The bug extends this tubelike appendage away from its body in order to feed. Such feeding tubes, modified for various piercing and sucking habits, are common to many (all?) of the true bugs, and smaller water striders are no exception. Enjoying a few moments of calm amid its adventure in the bowl of water, my strider took time to groom its lancelike mouthparts.
Back at the spring -- as if all the previous critters weren't enough -- I was fortunate to encounter yet another charismatic arthropod: a species of soldier fly (family Stratiomyidae), in larval form.
 |
| Larva of a soldier fly, family Stratiomyidae. See also: Adult stratiomyid and larva collected from a "tiny creeklet fed by seeps" in Story County, Iowa by MJ Hatfield, 2007 |
As I sat by the spring, it took me a while to see these critters, since they were rather cryptic and slow-moving; but once I saw them, I realized they were everywhere -- quietly scooting over the watery muck and cobbles, absorbed in the task at hand, which apparently involved feeding on minutiae too small for me to see. I posed this one on white paper and on an eyeglass lens in my home "bug studio."
Since I think these guys are way cool, I'm going all out with the photos. Here are my best attempts at a head shot of a live and active larva.
If you look closely, you can see the animal's eyes and antennae (yes, larval insects have antennae too!).
To be honest, observing them firsthand, I found these creatures to be a bit dopey -- but in a totally charming sort of way. And their feeding apparatus! It takes up much of the front of the head and quivers or palpitates rapidly as the larva moves about in search of food. Rudolf Rozkošný (1983) writes, "the mandibular-maxillary complexes [of stratiomyid larvae] are complicated structures with many setae, brushes, teeth or rows of projections in the molar area" (5). More easily than reading about them, though, you can get a sense for these larvae's crazy chompers by watching them in action -- here or here, for instance. (My bug videos aren't exactly studio quality, but I do hope you give them an chance when you can! Bugs are so much more interesting in motion!)
What exactly these larvae are collecting with all that fancy mouthwork, I'm not sure. However, algae are known to be the food of choice for soldier fly larvae that live on rocks covered in a thin film of water (6). Does the hillside spring along Ice Cave Rd qualify as that sort of hygropetric habitat? Another question I'm afraid I can't answer today.
But that's okay. Uncertainties and mysteries surround us in the study of life, and as collaborator MJ Hatfield likes to remind me, it's the mystery of it all that keeps us coming back. For example: How is it possible that the Universe could create an animal as delightfully ferocious as the one I'm about to show you?
This will be the final invertebrate from the hillside spring that I'll share with you on this post, and I do believe I've saved the best for last.
---
It's WEIRD!
It's TENTACLED!
 |
| Well, sort of. |
It might MAKE YOU SCREAM!
 |
| If you're half an inch tall and stuck in the water with it. |
It's...
...a predatory crane fly larva!
 |
| RAWR |
Oh my GOSH these things are cool.
Allow me to explain...
As I wrapped up my first visit to the hillside spring, I decided to bring a bit of it home with me. Mainly I wanted to rear the soldier fly larvae to adulthood, but I also figured there was probably some other interesting stuff hiding amid all the waterlogged muck and calcareous grit. So, I scooped up a few handfuls of the substrate and plopped it in a jar. Back at home I transferred this messy stuff to a shallow container. A few jewelweed sprouts survived the trip, and I "replanted" them.
If you look at the base of the twin sprouts near the top of the image above, can you see the wormy thing in the muck? It's a bit darker than its surroundings, and has some pinkish color to it.
I was pretty excited when I saw this; even though I had no idea what it was, it looked very interesting. I gingerly picked it out of the muck and dropped it into a bowl of water. What follows is the best shot I could get of the creature in the bowl, which writhed about as if unhappy to be plunked into such unfamiliar environs (imagine that!).
I posted this picture to the "ID Request" section of Bugguide.net, and within 24 hours a fellow contributor had identified the "wormy thing" -- to genus. (Bugguide is truly an impressive resource!) The animal was a species of Pedicia, one of the so-called "hairy-eyed" crane flies. This astounded me: I had no idea there were any fly larvae with such well-developed, pincer-like mouthparts. It seemed clear this was a predator; indeed, Bugguide's information page for Pedicia indicates that "larvae are strictly aquatic and predaceous, a good bioindicator of clean aquatic habitat" (7). What a beast!
In my Internet search for more information, I came across Jason Neuswanger's eye-popping photographs of a Pedicia larva. Besides greatly stoking my newfound enthusiasm for these flies, Jason's work really made me want to try for better photos of the larva I'd found. I never got around to it...but fortunately, when I returned to the spring a few weeks later and collected more substrate, a Pedicia larva turned up in the sample! It seemed like the perfect opportunity -- so I rigged up a teeny little aquarium and busted out my camera.
The first four Pedicia images above came out of that photo shoot; so did these:
Incredibly, the larva was able to completely retract its mouthparts into its front end:
And how about all those appendages on the rear end?
 |
| Bye bye, says Pedicia |
What a world.
---
Here's a photo of the hillside spring on April 24, roughly a month after I paid my first visit.
 |
| 24 April 2018 |
You might notice it looks less green than it did at the end of March! How did that happen?
Well, first, in early April we had two or three nights in a row with lows in the teens. Most of the jewelweed sprouts -- out in the open as they were -- didn't fare so well:
 |
| 8 April 2018 |
However, by some quirk of terrain -- or perhaps because they had sprouted amid last year's sprawling dead leaves of reed canary grass, and were thus slightly more sheltered -- some of these tough little seedlings survived.
 |
| Survivors, 8 April 2018 |
But that wasn't all our wintry April had in store for the life on this hillside spring. Heavy wet snow descended upon the Decorah area in mid-April, and one afternoon, with a thick covering of white smothering most of the hillside, I visited the spring again.
I was amazed by what I saw:
Birds! Everywhere!
 |
| Early migrant birds foraging in the hillside seep after a recent heavy snowfall, 15 April 2018 Bottom half of image: five American robins; top half of image: one American woodcock and one hermit thrush |
 |
| Fox sparrow, American robin, and American woodcock |
 |
| Two American woodcocks |
 |
| Two American robins (top and right) and a red-winged blackbird (bottom left) |
 |
| Common grackle |
Video of the woodcocks feeding at the spring (they strut and teeter!)
These early migrant birds had flocked to the spring because, so soon after the snowfall, it offered them one of the only areas of open ground they could find -- and, as a living landscape even at this difficult time, the saturated muck abounded in easily accessible seeds and insects. (Not to mention fresh water to drink!) It wasn't so great to know that scores of soldier fly and Pedicia larvae were likely getting gobbled up -- but I was really happy for the birds, that they could find such sustenance here.
And the jewelweed sprouts? Well, by the time I revisited their home on April 24, most of them had perished. But a healthy fraction had persisted -- despite the worst that early spring could hurl upon them. They had narrowly dodged getting frozen to death, smothered by snow, and trampeled by a horde of hungry and desperate birds. And now it was sunny and warm on the hillside spring; and it was time to continue -- time to stretch proudly and fully upward, into the season of life.
 |
| The toughest of the tough -- 24 April 2018 |
---
NOTES
Thank you to my fellow contributors at Bugguide.net for furnishing identifications of the animals mentioned in this post.
1. Runkel, S.T. and D.M. Roosa. 2010. Wildflowers and other plants of Iowa wetlands. University of Iowa Press: Iowa City. Link
2. Reed canary grass webpage at ISU EEOB's Grasses of Iowa project; see also this Iowa DNR factsheet
3. Lynch, E.A. and A.B. Weckwerth. 2017. Herbaceous vascular flora of forested seep wetlands in Winneshiek County, Iowa, USA. Jour. Iowa Acad. Sci. 124(1-4): 1-10.
4. Page 43 in Ivković, M., Stanković, V.M., and Z. Mihaljević. 2012. Emergence patterns and microhabitat preference of aquatic dance flies (Empididae; Clinocerinae and Hemerodromiinae) on a longitudinal gradient of barrage lake system. Limnologica 42(1): 43-49.
5. Page 214 in R. Rozkošný. 1983. A biosystematic study of the European Stratiomyidae (Diptera): volume 2. Springer Science & Business Media: 431 pp.
6. Ibid., p. 95
7. https://bugguide.net/node/view/14194
