Mosquitoes flee when they detect chemicals emitted by their predator, the N. maculata backswimmer.
From the sciencedaily.com
These odd insects, often lumped with their slender cousin, the backswimmer, are infamous for confounding anglers.
From the denverpost.com
When the arriving female mosquitoes detect a chemical emitted by the backswimmer, they are less likely to lay eggs in that pool.
From the sciencedaily.com
More examples
Predaceous aquatic insect that swims on its back and may inflict painful bites
Notonectidae is a cosmopolitan family of aquatic insects in the order Hemiptera, commonly called backswimmers because they swim upside down. They are all predators, up to nearly 2 cm in size. ...