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Toxotes jaculatrix

Toxotes jaculatrix
Banded Archer Fish
The banded archerfish (Toxotes jaculatrix) is a brackish water perciform fish of the archerfish genus Toxotes. It is silvery in colour and has a dorsal fin towards the posterior end. It has distinctive, semi-triangular markings along its sides. It is best known for its ability to spit a jet of water to "shoot down" prey. Larger specimens may be able to hit prey 2 to 3 metres (6 ft 7 in to 9 ft 10 in) away. The banded archerfish may reach the displaced prey within 50 milliseconds of its hitting the water.
The name (binomial as well as common) refers to Sagittarius the archer, because of the unusual method banded archerfish use to capture prey. Banded archerfish are found in Indo-Pacific and Oceanian waters, generally in river mouths and mangrove estuaries. They move between fresh, salt, and brackish water over the course of their lifetime, though not to breed. 
Banded archerfish have mouths adapted to spit jets of water over distance, usually to knock prey into the water. The banded archerfish shoots the jet of water by raising its tongue against the roof of its mouth, forming a tube. The opercula then close quickly, pressurizing water along the tube. Most archerfish are able to spit at a range of 150 centimetres (59 in), though some larger specimens may be capable of ranges of up to 2 to 3 metres (6 ft 7 in to 9 ft 10 in). When a prey is shot down, the banded archerfish begins to move towards the place where it will land within 100 milliseconds and can reach it within 50 ms of its hitting the water.
A study found that banded archerfish could be trained to hit moving targets at an accuracy rate of greater than 50%. According to this study, the ability to hit moving targets is a complex learned behaviour, and can be learnt from other members of the school. The study concluded that fish could shoot more accurately after observing other members of the school shooting.
The banded archerfish is able to hit targets with a high degree of accuracy, despite refraction of light in the water. It is believed that they are able to achieve this level of accuracy by positioning their bodies to shoot from directly under the intended target. However, other studies have found that banded archerfish are able to achieve great accuracy even at angles, suggesting that they are somehow able to compensate for refraction.This may also suggest that banded archerfish are capable of three-dimensional tasks
The banded archerfish inhabits the Indo-Pacific and waters off northern Australia, and less frequently those on the southern coast of Australia. It can be found from India eastwards to the Philippine Islands, southwards to Australia, as well as in waters off the Solomon Islands and the Indonesian Archipelago. It has been observed as far east as the New Hebrides (now known as Vanuatu). The banded archerfish occurs mainly in areas of brackish water. Mangrove estuaries are its primary habitat, though it occasionally moves upstream into freshwater rivers. It is associated with reefs and has been reported to occur near overhanging vegetation. While they may move between fresh and salt water during their life cycle, they do not do so to breed.
射水鱼俗称高射炮鱼,学名:Tax 射水鱼捕食otes jaculator,英文名:Archerfish,属于鲈形目射水鱼科,发现于1766年。射水鱼十分爱动、调皮,色彩鲜艳。身长只有20厘米左右,长着一对水泡眼,眼白上有一条条不断转动的竖纹,在水面游动时,不仅能看到水面的东西,也能察