The Great Biocube experiment

Excellent water scorpion. I remember catching those as a kid pretty often. Quite the predators.

Great shots, Mike!

1. to 4., Water Scorpion, Ranatra sp.

5. Caddisfly, Trichoptera: Limnephilidae (?)

6. Isopod, Asellidae

7. Damselfly, I think a Lestes sp. (spread-winged damselfly)

8. Yellow Bullhead, Ameiurus natalis

9. Green Frog, Lithobates clamitans

Good shots of the heads/faces of the isopod and damselfly could help get a definite genus ID.

The isopods don't last long. The sunnies harrass them and the Ranatra spears them. The four perch bugs [dragonfly larvae] are still in the tank. I never knew they were sit&wait predators that buries themselves in the substrate. I pictured them much more active. Trying for photos.

I spent WAAAY too long trying to get the damsal face pics. All my life I've seen those guys, even tried tying flies to imitate them, and I had no clue how cool their faces are!

Were you aware that the green frog tads were aggressive egg eaters? I sure was not. Actually, they seemed to eat only the jelly. The sunnies and big inverts then ate the exposed embryos. I also have a smaller more colorful tad which nibbled the jelly.
At the time I got the tads from a pond in early spring, I wondered why would overwinter in a fish filled pond. I know believe they overwinter to be in place when the yellow perch lay their jelly encased eggs in late winter.
The green frogs must do alot of damage when they can successfully overwinter in the more persistent vernal pools.
But I'm getting ahead of myself....

I prodded this dragonfly larvae out because he just looked like a bump on the bottom. He settles himself into the sand like a flounder. Not what I expected at all.

He's so photogenic. He leaves the fish alone but it's hard to keep enough isopods for him.


Colorful boatman.

What are the spotted beetles? No fish or bug can eat them.

My favorite Star Wars creature. I love adult damsals. I never looked so close at the larvae. I hope he emerges for me. How long is the cycle?


Which part is the mouth?

That's definitely a Lestes. The labium is jointed and extensible; the long downward projection below the head is the folded "arm" of the labium, with the "elbow" at the bottom. The business end of the labium is held over the face like a mask. The damsel captures prey by swiftly unfolding the labium and spearing/snagging the prey with the claws at the end of the labium. Dragonfly naiads have the same structure, though it tends to be broad and shovel-like in them; the folded labium looks like a muzzle. Your dragonflies are probably skimmers (Libellulidae).

Odonates typically have cycles of several months to a year. Your guy definitely has a ways to go. You can judge development to some degree by watching the size of the wing pads on the thorax.

Green frog tads are definitely egg lovers, as are many other tadpoles (and newts, garter snakes, leeches, etc.). You can sometimes find them gathered around an ovipositing frog or salamander, devouring the eggs as they are laid. Amphibian eggs are one of the biggest nutrient inputs in a lot of ponds, and are often available in the earliest spring before the algae has really taken off. Green frogs and bullfrogs typically overwinter whatever the pond conditions; they are not rapid developers like toads and treefrogs that can be in and out in just a few weeks.

Those little seed-like swimming beetles are mostly dytiscids (a family which also includes some of the largest aquatic beetles). I don't know which genus yours are.

That's definitely a Lestes. The labium is jointed and extensible; the long downward projection below the head is the folded "arm" of the labium, with the "elbow" at the bottom. The business end of the labium is held over the face like a mask. The damsel captures prey by swiftly unfolding the labium and spearing/snagging the prey with the claws at the end of the labium. Dragonfly naiads have the same structure, though it tends to be broad and shovel-like in them; the folded labium looks like a muzzle. Your dragonflies are probably skimmers (Libellulidae).

Odonates typically have cycles of several months to a year. Your guy definitely has a ways to go. You can judge development to some degree by watching the size of the wing pads on the thorax.

Green frog tads are definitely egg lovers, as are many other tadpoles (and newts, garter snakes, leeches, etc.). You can sometimes find them gathered around an ovipositing frog or salamander, devouring the eggs as they are laid. Amphibian eggs are one of the biggest nutrient inputs in a lot of ponds, and are often available in the earliest spring before the algae has really taken off. Green frogs and bullfrogs typically overwinter whatever the pond conditions; they are not rapid developers like toads and treefrogs that can be in and out in just a few weeks.


Those little seed-like swimming beetles are mostly dytiscids (a family which also includes some of the largest aquatic beetles). I don't know which genus yours are.

Thanks yet again! I have to admit, being pressed for time,, letting you fill me in is saving me hours and hours of research. I still have to go back and add all the ids to the FB album to help disseminate some of the knowledge.

This whole thing is really opening my eyes to a world I already thought I knew but had barely scratched.
How I didn't know [or forgot] green frog tads eat eggs surprises me. I've had so many tadpoles going back to pickle jars in grade school, fed a few hundred to fish and herps over the years, dumped a thousand from my dip nets and not only did not know about the egg eating, I've never looked at their mouth parts before!
I've got some cool pics of the egg eating, maybe tonight or tomorrow lunch.
Thanks again Nate

Forgot to add, I have seen all the fish plus the scorpion and the damsal larvae [to fast for my eye] snag those little dytiscid beetles. All have released them. I still have everyone that got in.

Edited by mikez, 29 March 2010 - 11:16 AM.

Forgot to add, I have seen all the fish plus the scorpion and the damsal larvae [to fast for my eye] snag those little dytiscid beetles. All have released them. I still have everyone that got in.

Got any little red water mites in there yet? I had one come in with plants a few years ago, and it was pretty cool to see fish check it out over-and-over, but never actually eat it. They're tiny and soft-bodied, so it's definitely a chemical defense rather than mechanical. Wonder if it's taste or texture that keeps your beetles alive?

I'm not sure on that. They are hard little things- possibly too tough for some critters to swallow or too slick to hold. A lot of beetles have chemical as well as physical defenses. Next time you scoop up some whirligig beetles in your net, give 'em a sniff; the small Gyrinus species smell musky, the larger Dineutus like green apples. Not much seems to eat them, though something must as they still have behavioral responses to possible predator approaches.

Being raised a flyfisherman from childhood, I can't help but see tiny beautiful emergent winged insects as the ultimate, the elite of the invertebrate world.
I've always enjoyed the occasional flier that turned up in the house after adding live food or pond plants. My wife, not so much. If the midges didn't look so much like mosquitoes and the moths didn't look just like grain moths, she might have tolerated them better.

I noticed two of these guys on the glass in the tank toady. Size of smaller mosquitoes. The color is really cool in person. This is lepidoptera, right?
Couldn't possibly be the two huge caddis larvae that recently went missing? Size difference seems too extreme.

Hard to believe two larvae survived and emerged with out getting eaten. And the sun fish are never hungry and are never fed.
Side note, the sun fish ate the damsalfly larvae and I found the water scorpion on the screen in my kitchen window after leaving the cover off the tank one warm day. Only fair thing to do was open the screen and wish him luck.

I noticed two of these guys on the glass in the tank toady. Size of smaller mosquitoes. The color is really cool in person. This is lepidoptera, right?

Great pictures, I love the colors on those. Those are actually diptera though. Some type of midge.

Side note, the sun fish ate the damsalfly larvae and I found the water scorpion on the screen in my kitchen window after leaving the cover off the tank one warm day. Only fair thing to do was open the screen and wish him luck.

At least you found your's on the screen. I had one that disappeared several years back. I searched all the windows and light fixtures in the house and never did find it.