Did you "Flip A Rock" today?

Today is International Rock Flipping Day. In celebration, I went outside to flip a rock and see what lived beneath.





Here is the rock, in situ (in place), at the edge of my pond in southwest Ohio:


When I flipped it over, the first thing I saw were two aquatic "bugs" on the underside of the rock. (One crawled away before I could take the picture.) They reminded me of pill bugs (woodlice, sowbugs, "rolly pollies," pick your local nickname) so I assume they are an aquatic form of this crustacean. The head is green and the body a purplish-brown. My macro function isn't too great, so enlarging this picture will just get you an out-of-focus view, but if anybody can ID this critter, I would appreciate it.

[Edit: In looking more closely, I see legs.
I now realize this is insect-like, not an isopod.]

As I started to replace the rock, I saw something moving. At first, I thought it was a bit of plant matter, twirling in the residual vortex created when I flipped the rock, but then I realized it had purposeful movement.

Here is the thing enlarged.

I even got a little video clip of the grub-thing in action.



It made me think of a warble, the larval form of the rabbit botfly Cuterebra, which I sometimes see in cats. Does anyone know what this "water grub" might be?

[Edit: Thanks to a comment by Cestoady, I have ID'd the grub-thing. While researching the suggestion of tipulid, or Crane-fly larvae, I found it on What's That Bug? (5th image as you scroll down) It is the larva of a horsefly, which I have in abundance here since the Purple Martins left. Good thing I didn't try to touch it - they bite, injecting a toxin which causes extreme and prolonged pain and swelling, according to this entry at Bug Guide.]

If you would like to participate in the second annual International Rock Flipping Day, please click here for the guidelines. Then, go flip over a rock and see what you can find. Come back and share your observations with the rest of us, by posting your link in the comments section or by sending a link to your post to Dave.

Don't forget to put the rock back!

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9/8/08:

Here's a list of recent rock-flipping sites to visit:

Pohanginapete (Pohangina Valley, Aotearoa/New Zealand)
Blaugustine (London, England)
Nature Remains (Ohio, USA)
Pensacola Daily Photo (Florida, USA)
KatDoc’s World (Ohio, USA)
Notes from the Cloud Messenger (Ontario, Canada)
Brittle Road (Texas [?])
Sherry Chandler (Kentucky, USA)
osage + orange (Illinois, USA)
Rock Paper Lizard (British Columbia, Canada)
The Crafty H (Virginia, USA)
Chicken Spaghetti (Connecticut, USA)
A Passion for Nature (New York, USA)
The Dog Geek (Virginia, USA)
Blue Ridge blog (North Carolina, USA)
Bug Girl’s Blog (Michigan, USA)
chatoyance (Austin, Texas)
Riverside Rambles (Missouri, USA)
Pines Above Snow(Maryland, USA)
Beth’s stories (Maine, USA)
A Honey of an Anklet (Virginia, USA)
Wanderin’ Weeta (British Columbia, Canada)
Fate, Felicity, or Fluke (Oregon, USA)
The Northwest Nature Nut (Oregon, USA)
Roundrock Journal (Missouri, USA)
The New Dharma Bums (California, USA)
The Marvelous in Nature (Ontario, Canada)
Via Negativa (Pennsylvania, USA)
Mrs. Gray’s class, Beatty-Warren Middle School (Pennsylvania, USA)
Cicero Sings (British Columbia, Canada)
Pocahontas County Fair (West Virginia, USA)
Let’s Paint Nature (Illinois, USA)
Sleeping in the Heartland (Midwestern U.S.)
Three Oaks (Ohio, USA)