water scorpion

noun

1. any of various long-legged aquatic insects of the heteropterous family Nepidae, which breathe by means of a long spinelike tube that projects from the rear of the body and penetrates the surface of the water

Example Sentences

"We've got damselflies and dragonflies, little water boatmen, whirligig beetles, water scorpions and because of all of them, we get all the birds that feed off them," he says.

From BBC

We have already noted the size of the earlier water scorpions.

From Project Gutenberg