Sunday, August 7, 2016

100 Common Insects of Arkansas and the MidSouth (continued)

As you can see by the new title for our insect book, it has gotten longer and covers a larger area. We kept seeing creatures we wanted to add. It's probably over a hundred now. Cheryl is helping me clean up syntax, and especially, when I hit something I don't know, making sure I do some research instead of, as I usually do, making up an answer. As Huck said, it's mainly true with a few stretchers.







Wheel Bug, Arilus Cristatus


This insect is in the order Hemiptera, or "the true bugs." Colloquially, all insects are called "bugs," but technically, the true bugs are only those in this order, and are marked by having the basal half of the forewings leathery and the outer half membranous, a segmented beak that folds under the chin when not in use, and they do not have complete metamorphosis, hatching out of the egg more or less like a small version of the adult. Some use their beaks to suck plant juices, some to suck the juices of their prey. The Wheel Bug is one of the latter.

If you have a garden (that you don't pour a lot of poisons into), you will be sure to have seen this big (over an inch long) bug with what looks like a half saw-blade on the back of its thorax. The long beak looks formidable and it really is. If you try to pick it up and it gives you a jab it will make you yell. They use it to kill their prey (chiefly caterpillars) and turn the insides into soup which they suck dry. I don't mean you should be stamping on them, I mean you should be admiring them as powerful actors in the natural system around you which needs a balance between survivors and population controllers.








Eight-spotted Forester, Alypia octomaculata


Here is a very handsome and commonly seen day-flying moth. Most moths are secretive, but this one WANTS to be seen. Black white and red is a color-scheme well known throughout nature, to birds, lizards, insects, spiders, even human beings (think of bees and wasps: we see black and orange or black and yellow bands, and we know not to touch). These are warning colors; it's technically called aposematic coloration. Some combination of black and white and orange-red means "Don't touch me, I have a nasty bite, or an envenomed sting, or I taste terrible to the point of being poisonous." Sometimes they are just pretending with their colors, and can't hurt you or don't taste bad, but who wants to take the chance?








Bald-faced Hornet, Dolichovespula maculata



These make the basketball-sized paper nests hidden in bushy foliage (only coming into view when leaves are lost in autumn). I remember finding a nest in mid-winter (the inhabitants presumably dead and gone) and bringing it home and setting it attractively in a corner of my study, only to learn, when the room had warmed up to spring-like temperature, that a couple of dozen pregnant queens waiting for next year were overwintering in the nest and were now all emerging early and in very bad tempers.

These hornets are meat-eaters and the workers go out and catch horse flies or butterflies or whatever insects they can and tear them up in pieces and bring them back to the nest. They have a special trick. On cold mornings they can, by shivering, warm themselves up to mammal-like temperatures. They then go out and look for insects that are too cold to fly away. You can see them flying along and smashing into every black spot they see on a leaf, in case it is a tasty insect.

(I didn't realize until I put that picture up how much it looked like a gorilla wrapped to be a mummy,)








Paper Wasp, Polistes metricus


There are several species of Polistes paper wasps. You might see them early in spring scraping fiber off smooth wood or plant stocks, which they mix with their saliva and make into a heavy gray paper, called carton. With it they make the pizza-shaped open nests that are hung from foliage, or often under the eaves of your house. There is a large all red species (P. carolinus) which I prevent from nesting around our house, since they tend to attack us, but the others (with various patterns of black, yellow, and red) are inoffensive and we enjoy watching them develop. The nest here is in an early stage. The over-wintered pregnant queen started this nest by herself and raised the first few workers. This is the perilous time and many nests fail, but she has made it through. Up near the top of the picture you can see eggs inside the cells, and a newly hatched grub. Below, a fully developed grub is spinning a cocoon around itself. Then there are three closed cocoons developing. The dark smudge at the top of the nest is the queen herself, resting on the stem that supports the nest. She no longer has to risk her life going out and foraging. Her job now is to stay there laying eggs while the others bring caterpillars and other insects to feed the babies like birds in a nest. There may be fifty or so workers by the end of the season.








Paper Wasp, continued, Polistes exclamans




Here is a mature nest in September. It looks to me like the flight deck of an aircraft carrier, ready for combat. When I got under the nest, which is in the eaves of the house, they all snapped to attention, and if you look you can see almost every one is staring straight at me. This is a peaceful species, but I didn't go any closer.








Paper Wasps, Polistes spp. (continued)



At the end of the season the queen and all the workers will die, but before they do they begin producing males and virgin queens. As it starts getting colder the virgin queens begin looking for sheltered places to hibernate in, hollow logs or, particularly, insides of buildings, attics or openings in the eaves. As they find these places, it turns out the males (identifiable by their white faces) are already waiting to waylay them and won't let them in till they have mated. The males then die, and the pregnant queens winter in the shelters, then emerge the following spring to start a new generation.



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