Mosquitoes. They ruin your picnics, disrupt your naps and suck your blood. Although they measure less than an inch long at most, they kill more people than any other animal, up to 700,000 a year. They're responsible for the spread of diseases including, but not limited to, malaria, yellow fever, Chikungunya, West Nile virus, dengue fever, filariasis, and the Zika virus, and statistically, they basically caused the most deaths to humans by animals (even more than snakes). Expect to hear them long before you see them and the characters to run away in a hand swatting panic when they swarm on them; some might be covered in a plethora of bites when it's all over. Even if the situation isn't dire, expect someone to be immensely bothered by the tiny terrors. Typically found in nasty swamps or the rainforest.
In real life, only the female mosquito sucks blood, and even then, only when she's going to lay eggs; the rest of the time she's a pollen feeder. If a male mosquito bites someone, it's case of Insect Gender-Bender.
Compare Macabre Moth Motif and Moth Menace, which give the "bad insect" treatment to moths, Flies Equals Evil for the mosquitoes' equally unpleasant relatives, and Bloodsucking Bats and Vampiric Draining, for other bloodsucking creatures in fiction.
- In this commercial for the Sega Genesis, a mosquito appears, sucking the blood of a gamer, which the announcer uses as an analogy for being charged up to $10.00 more to play games like Mortal Kombat and NBA Jam on the Super Nintendo Entertainment System than on the Genesis. The mosquito appears looking quite plump, until the gamer swats it with a newspaper that says, WELCO METOT HENEX TLEVEL, Sega's slogan at the time, in the crossword puzzle section.
- One-Punch Man: One of the first villains fought by Genos was a mosquito-woman, who ends up surviving but with major damage.
- Hunter × Hunter gives us a human-mosquito Chimera Ant early in the titular arc, a very Ax-Crazy Laughing Mad one at that, which winds up being killed by Killua.
- Soul Eater: The aptly named Mosquito is The Dragon to Big Bad Wannabe Arachne, and has a mosquito/vampire motif, and drinks his victims' blood from his Gag Nose.
- Yu Gi Oh Zexal has Mosquito Ninja (Scritch in the dub), a duelist who's Animal Motif is mosquitoes and turns into a Half-Human Hybrid of one when dueling and can inject hallucinogens into opponents.
- Cloudy with a Chance of Meatballs 2 features Mosqui-toasts, which are mosquitoes with toast for bodies, and, while not particularly dangerous, are just as annoying as normal mosquitoes.
- In Lilo & Stitch, Pleakley believes that mosquitoes are an endangered species, but changes his mind after getting up close and personal with them in Hawaii.
- One of the villain's henchmen in Fleischer Studios' Mr. Bug Goes to Town is a mosquito named Smack and the miscreant stereotype seems to apply to the insect world, along with the fly named Swat, too, as he doesn't wish to be seen hanging out with them.
- "Self Service", a short by Bruno Bozzetto. The little pests make a whole capitalistic dream out of their source. Until it runs dry...
- The Scar: The Anophelii are a Dying Race of humanoid mosquitoes who once ravaged the continent in a nightmarish "Malarial Queendom". The females are so consumed by their Horror Hunger that they're nearly mindless and will exsanguinate anyone they can reach in seconds. Zig-zagged with the males, who are peaceful, vegetarian scholars.
- Ann Leckie's The Raven Tower: Inverted with the Physical Goddess known as "The Myriad", who prefers to manifest as vast clouds of mosquitoes, but is a Creepy Good friend of the narrator and a faithful patron to her human worshipers. However, it's mentioned that her name is used as a curse in other lands, so she might play the trope straight for those who don't enjoy her patronage.
- Dungeons & Dragons, Advanced D&D supplement Deities & Demigods Cyclopedia: In the Melnibonean Mythos section, Nnuuurrrr'c'c is the master of all swarming insects. It takes the form of a 40-foot-tall mosquito that can kill any creature by draining its blood.
- Pathfinder: The Lawful Evil swamp blights are always surrounded by, and can control, clouds of biting mosquitoes.
- In Best Fiends, the antagonistic past of Edward the mosquito is hinted at through his bio. In the present of the game, he has changed his ways against sucking blood, and is also the mascot of the Malaria No More movement the game helps sponsor.
- Darkest Dungeon: The antagonists from the first DLC are mosquito-themed vampires.
- In Dark Souls, the Blighttown is infested with giant mosquitoes which can inflict poison by biting you or spitting their blood at you. They also respawn frequently, almost immediately after killing one. Thankfully, they don't respawn indefinitely and each mosquito only respawns for up to 7 times.
- Diablo II has Giant Mosquitoes, monsters found only in Act 3, and Swarms, monsters found in Acts 2-4. Both of them are capable of draining stamina from the player when attacking.
- The PC Mega Man (Classic) games made by Hi Tech Expressions under license of Creator/Capcom feature various nature menaces instead of robots, including giant mosquitoes that are hard to be killed, as many of the enemies of those games.
- Pokémon Sun and Moon introduces the Ultra Beast Buzzwole, a hulking alien abomination that resembles a mosquito. While not overtly "evil", it is aggressive, and the player must subdue it like the other Ultra Beasts.
- Sonic the Hedgehog: In Sonic CD, the Needlenose enemy is a robotic mosquito that plunges down at Sonic if he gets near him. This badnik re-appears in Sonic Triple Trouble and Knuckles Chaotix.
- Rayman: The first mini-boss Rayman faces is Bzzit, a giant mosquito. After beating and befriending Bzzit he helps Rayman through the Dream Forest to face Moskito, a red-colored mosquito that serves as the first boss in the game.
- In the Unreal series there's the Razor Fly creature, often simply called Fly. It's a small-to-medium sized fly creature that can be defeated with three Enforcer shots and whose only attack is to ram upon the player and hit them with their tail. In certain levels, some actions will trigger a swarm of these. Mosquitoes can be found in the outdoor levels of the game, and in the Chizra - Nali Water God ancient temple, among other natural locations of Na Pali, and in later games in the Invasion gametype as one of the regular mooks that spawn.
- In The Huckleberry Hound Show, episode "Skeeter Trouble", Huck's camping trip is thrown into chaos when a mosquito continuously tries to bite his nose. Things get worse later when a whole swarm comes after him.
- In the Camp Lazlo episode "Lumpy Treasure", Raj gets bitten by a multitude of mosquitoes on his butt and the bites form the shape of a treasure map. When the Jelly Bean trio finds the treasure at the end the mosquitoes take it for themselves.
- The Simpsons: In one episode (Little Girl in the Big Ten), Bart is bitten by a foreign mosquito that stowed away in a toy he got at the Krusty Burger and becomes very sick. He gets quarantined in a bubble out of fear that the disease is contagious.
- The Chip 'n Dale Rescue Rangers episode "Chocolate Chips" has a swarm of mosquitoes as the minions of a German chocolatier. Their function: to administer the chocolatier's mind control juice to his zombie slaves.
- Kid vs. Kat: In "Buzz Off", Kat turns two mosquitoes gigantic from them drinking his Alien Blood and uses them to attack Coop, only for the latter to take control of one of them and engage Kat in a dogfight. The two mosquitoes turn on both of them after being mistreated and deciding they're done being told what to do.
- Mosquitos appear in the Private Snafu shorts "Private Snafu vs. Malaria Mike", "Target Snafu" and "It's Murder She Says", which are all the prevention of malaria and other mosquito-borne diseases.
- The Looney Tunes short "Of Thee I Sting" features mosquitos as an air force squadron training for a mission.
- In the Rugrats episode, "Angelica Nose Best", a mosquito bites Angelica's nose when she's asleep. She doesn't get sick, but it does swell up and she thinks it's because she lies, like Pinocchio.