Sweating the Small Stuff: July, 2011

Here is a continuation of my review of 2011. The month of July.

The month begins with some interesting caterpillars. The first is a Walnut Caterpillar. It's a quite wonderful hairy thing.

These feed on the leaves of walnut and pecan and other types of nut trees. They often appear in a tree by the dozens or hundreds clustered fairly closely together. They have an amazing defense maneuver. When some predator approaches, the individual caterpillar twitches its body violently about once a second. No one knows how they coordinate this, but every caterpillar in the tree begins the body twitch, and they do it in exact synchrony, so that instead of each one looking like a vulnerable and helpless creature, it looks like they are all one big breathing animal. I suspect it might frighten off a bird. But when we have come over to watch this behavior closely, it has usually been parasitic ichneumon wasps attacking them, and the wasps didn't seem to be very impressed.

But the next caterpillar is our absolute favorite of all. It's called The Laugher, and this picture will show you why.

Look at the horrible "teeth" from close up. This guy's been on crystal meths half his life.

Here's another of the dozen or so bumble bee-mimicking robber flies in the genus Laphria that are found in Arkansas. This is Laphria lata.

Plains Clubtail, female, Gomphus externus.

The robber fly Ommatius ouachitensis, eating a midge. Both these creatures have feathery antennae.

The male of the Zabulon Skipper is a small bright yellow and orange butterfly that sets up a territory and drives off everything, including you, that comes too close. The dowdy brown female is the opposite in personality, slipping around quietly down in the shadows. But looked at closely, as here, she is pretty in her own way.

Here's another special caterpillar, the Spiny Oak-Slug, Euclea delphinii. These atypical moth caterpillars have no legs but slip around sort of like slugs. They are cute, but don't touch. They are armed with stinging spines.

Argiope aurantia, the Black-and-yellow Garden Spider, with a large katydid.

This fancy wasp has a fancy name, Gnamptopelta obsidianator. The larvae are internal parasites of caterpillars.

Here's a Spot-winged Glider, Pantala hymenaea. On warm days these and their near relatives, the Wandering Gliders, can fill the sky with their swarms.

Promachus fitchii, a handsome robber fly of prairies.

A Seaside Grasshopper disappearing into its background.

Efferia aestuans, female, a rather natty robber fly. Females of the genus Efferia feature long ovipositors.

The robber fly Holcocephala, sometimes called the Goggle Eye. This species is in the subfamily Trigonomiminae, and though there is some debate on this, this is possibly the basic robber fly group from which all other robber flies derive.

Trapdoor Spiders, big black tarantula-like spiders, spend most of their time waiting inside a tube just below the surface of the ground. When some insect comes jauntily strolling by, they suddenly raise the lid of the carefully concealed trap door, rush out, grab the hapless insect, and drag it struggling back down underground, and close the trap door behind them. It all happens so quickly you think you've only imagined it, and if witnessed, is the arachnophobe's nightmare come true. We saw this trapdoor spider during one of its occasional wanderings above ground.

This is a Dusky Dancer, Argia translata, a damselfly with beautiful violet eyes.

Here is the female ovipositing her eggs in the water, the male holding onto her with claspers on the end of his abdomen. He is not bravely protecting her from drowning, he's just keeping a hold on her so no other males try to get in on the act.

A large powerful dragonfly, the Gray Petaltail, Tachopteryx thoreyi, killing a big grasshopper. Dragonflies are among the most primitive insects, and this is the most primitive species of dragonfly.

The Powdered Dancer, Argia moesta, gets its name because as it gets older it gets more covered by a powdery bloom which renders its pattern indistinct.

The Red-legged Grasshopper, Melanoplus femurrubrum (the red is on the hind legs so you can't see it here), is a member of one of the main subfamilies of grasshoppers, the "Spurthroats." The picture shows, between the front pair of legs, the "spur" for which they are named. But while we are looking at this close-up, notice something else: Insects evidently evolved from a centipede-like creature that had many segments, and a pair of legs on each segment. As insects developed, they collapsed the number of segments into fewer but more complex parts, and did away with all but six legs. But sometimes the legs, instead of disappearing, were co-opted into other jobs. You can easily see here two pairs of what once were legs are arranged around the mouth and are now used to help shovel in food.