from The American Heritage® Dictionary of the English Language, 5th Edition.
- noun Any of various predatory hemipteran insects of the family Notonectidae that live in freshwater habitats and swim on their backs by means of oarlike hind legs.
from The Century Dictionary.
- noun Same as
from the GNU version of the Collaborative International Dictionary of English.
- noun any of numerous predaceous aquatic insects of the family
Notonectidae(such as Notonecta undulata) that swim on their backs and may inflict painful bites; -- also called boat bug.
from Wiktionary, Creative Commons Attribution/Share-Alike License.
- noun Any of various
aquatic insects, of the family Notonectidae, that swimon their backs.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- noun predaceous aquatic insect that swims on its back and may inflict painful bites
from Wiktionary, Creative Commons Attribution/Share-Alike License
Scientists have found that an aquatic insect known as a backswimmer, which is similar a water boatman, releases a "scent" that scares off mosquitoes - although it cannot be picked up by the human nose.
Previous research from Blaustein's lab demonstrated that the mosquito, Culiseta longiareolata, chemically detects a voracious predator of its progeny in the water, the backswimmer, Notonecta maculata, and avoids laying eggs where the predator is detected.
While many say that water boatmen do not bite and are often confused with the backswimmer, I am sure that the insects in the pool were water boatmen, so I would urge some care in handling them if you come across them and want to take a closer look.