I think many people who visit Iraq have been alarmed by a particularly large and nasty looking wasp. They are reddish brown and yellow and have a habit of buzzing around you ominously. Our PAs called them "the meat eaters" because on several occasions they saw them making off with large chunks of hotdog or hamburger that was left outside. Since I had a bug net I caught quite a few of these critters during my time there.
These were Oriental Hornets (Vespa orientalis). Some of them were 2 inches long with 3 inch wingspans. Pretty formidable when its flying around your tent. I was never stung but they can pack a wallop.
In the other stinging critter arena I found a nice poster put out by the army on Arachnids of Iraq. The pictures of the scorpions, spiders and camel spiders are great.