The archerfish (Toxotes) is a species of fish found in many estuaries and mangroves worldwide. They can be found from India and Sri Lanka, through Southeast Asia, to Northern Australia and Melanesia. The archerfish gets its name from the jets of water it spews from it specialized mouth to capture prey.
Archerfish bodies are deep and laterally compressed, with the dorsal fin, and the profile of a straight line from dorsal fin to mouth. The mouth is protractile, and the lower jaw juts out. Sizes are fairly small, typically up to about 12–18cm. Archerfish have a silver body with an iridescent brown color with black stripes running down its body.
According to many different studies, archerfish are remarkably accurate in their shooting. An adult fish almost always hits the target on the first shot. They can bring down insects and other prey up to 3m above the water’s surface. This is partially due to their good eyesight, but also to their ability to compensate for the refraction of light as it passes through the air-water interface when aiming at their prey. They typically spit at prey at a mean angle of about 74° from the horizontal but can still aim accurately when spitting at angles between 45° and 110°. An archerfish will often leap out of the water and grab an insect in its mouth if it happens to be within reach. Individuals typically prefer to remain close to the surface of the water
When an archerfish selects its prey, it rotates its eye so that the image of the prey falls on a particular portion of the eye in the ventral temporal periphery of the retina, and its lips just break the surface, squirting a jet of water at its victim. The archerfish does this by forming a small groove in the roof of its mouth and its tongue into a narrow channel. It then fires by contracting its gill covers and forcing water through the channel, shooting a stream that, shaped by its mouth parts, travels faster at the rear than at the front. This speed differential causes the stream to become a blob directly before impact as the slower leading water is overtaken by the faster trailing water, and it is varied by the fish to account for differences in range.
Archerfish are popular aquarium fish due to their size and remarkable abilities, but they are difficult to feed since they prefer live prey.