# Mosquito (*Culicidae*) > Mosquitoes are small biting flies of the family Culicidae, only about 3 to 6 mm long, found worldwide wherever there is standing water. Both sexes feed on nectar, but females also drink blood to develop their eggs, and in doing so they spread diseases such as malaria that make the mosquito the deadliest animal to humans. Adults fly slowly, at around 2.5 km/h (1.5 mph), and live only a few weeks. The IUCN lists them as Least Concern. - **Category:** Insect - **Conservation status (IUCN):** Least Concern - **Range:** Found worldwide except Antarctica, breeding in standing water from the tropics to temperate zones. - **Canonical page:** https://globalanimalguide.org/animals/mosquito/ - **Last reviewed:** 2026-07-16 ## Scientific classification - **Kingdom:** Animalia - **Phylum:** Arthropoda - **Class:** Insecta - **Order:** Diptera - **Family:** Culicidae ## Facts at a glance | Attribute | Value | | --- | --- | | Scientific name | Family Culicidae | | Diet | Nectar; females also drink blood | | Habitat | Worldwide near standing water | | Lifespan | Adults a few weeks | | Size | About 3–6 mm long | | Top speed | ~2.5 km/h (1.5 mph) | | Conservation status | Least Concern (IUCN) | ## Size and appearance Mosquitoes are tiny, delicate flies, typically just 3 to 6 mm long and weighing only a few millionths of a kilogram. They have a slender body, long thread-like legs, a single pair of narrow wings, and a prominent tube-shaped mouthpart called a proboscis. Females use the proboscis to pierce skin and draw blood, while males lack the equipment to bite. Their fragile build and light weight let them fly and settle almost unnoticed. ## Feeding and why females bite Both male and female mosquitoes feed mainly on flower nectar and plant sugars for energy. Only females bite, and they do so to obtain the protein in blood needed to develop their eggs. A female locates a host using body heat, exhaled carbon dioxide, and scent, then injects saliva that stops the blood from clotting as she feeds. It is this saliva, and the biting itself, that can pass on disease. ## Flight and behaviour Mosquitoes are weak, slow fliers that move at only about 2.5 km/h (1.5 mph), relying on stealth rather than speed. Their wings beat several hundred times a second, producing the familiar high-pitched whine. Many species are most active at dawn and dusk or through the night, resting in cool, shaded spots during the heat of the day. They tend to stay close to the damp places where they hatched. ## Life cycle and standing water Mosquitoes need standing water to breed, which is why they are found near ponds, marshes, ditches, and even water-filled containers. Females lay their eggs on or near the water, and the larvae, known as wrigglers, live in it while feeding on tiny organic matter. After a pupal stage the adult emerges to fly away, completing the cycle in as little as one to two weeks in warm conditions. Adult mosquitoes live only a few weeks. ## The deadliest animal to humans Though tiny, the mosquito is often called the deadliest animal on Earth because of the diseases it carries between people. Different species transmit malaria, dengue, yellow fever, Zika, and West Nile virus, causing hundreds of thousands of human deaths every year. The mosquito itself does not cause the illness, but acts as a carrier that passes microscopic parasites and viruses from one host to the next. This makes mosquito control a major focus of public health worldwide. ## Role in nature Despite their reputation, mosquitoes are part of many food webs. Their aquatic larvae are eaten by fish and other water creatures, and the adults are food for birds, bats, dragonflies, and spiders. Male mosquitoes, and females between blood meals, also visit flowers and can act as minor pollinators. The family Culicidae is widespread and abundant, and the IUCN lists mosquitoes as Least Concern. ## Frequently asked questions ### Why do mosquitoes bite humans? Only female mosquitoes bite, and they do so to get the protein in blood needed to develop their eggs. Both males and females otherwise feed on nectar and plant sugars. ### Are mosquitoes really the deadliest animal? Yes. Mosquitoes are often called the deadliest animal to humans because they spread diseases such as malaria, dengue, and yellow fever, causing hundreds of thousands of deaths each year. ### How long do mosquitoes live? Adult mosquitoes live only a few weeks. In warm conditions the whole life cycle, from egg through larva and pupa to adult, can be completed in as little as one to two weeks. ### Why do mosquitoes need standing water? Mosquitoes lay their eggs on or near standing water, and the larvae develop in it. Removing sources of still water is one of the most effective ways to reduce mosquito numbers. ### How fast can a mosquito fly? Mosquitoes are slow fliers, moving at only about 2.5 km/h (1.5 mph). They rely on stealth and their small size rather than speed to reach a host. ### Do all mosquitoes spread disease? No. Only certain species, and only biting females, transmit diseases, and only when they have picked up a parasite or virus from an infected host. Many mosquitoes never spread any illness. ## Sources - [IUCN Red List — Culicidae.](https://www.iucnredlist.org/search?query=Culicidae&searchType=species) - [Wikipedia — Mosquito.](https://en.wikipedia.org/wiki/Mosquito) --- Source: Global Animal Guide (https://globalanimalguide.org/animals/mosquito/). Licensed CC BY-NC 4.0 — free for non-commercial reuse with attribution.