Several days ago Betsy and I were visiting the Boyce Thompson Arboretum. As we sat on the shore of Ayer Lake, a fairly large insect suddenly flew in and splashed down in the water in front of us. I looked to see what was going on, and saw a water scorpion folding its wings and submerging itself into the waters of the lake. Here are a few pictures I took of this interesting beast:
The water scorpion is in the order Hemiptera – thus it's one of the true "bugs" of the insect world. It is called a water scorpion, but this guy is in the genus Ranatra – whose species are long and slender. To me it looks more like a "water stick insect" or a "water praying mantis." On the other hand, species in the genus Nepa are broad, and look a bit more like a scorpion. The reason species in either genus are called "scorpions" is because of their long thin "tail," which is really a breathing tube and does not carry a stinger. Thus, their common name is truly a misnomer.
Water scorpions generally eat invertebrates, but may occasionally take a small fish or tadpole. I hope they're not eating the endangered pupfish in Ayer Lake.
They are supposedly docile when handled carefully – though I didn't put that to the test. They are also noted for delivering a very painful bite. Fortunately, I didn't put that to the test, either.