Toxotes jaculatrix

Toxotes jaculatrix

13/04/2021 Off By Alina Novikova

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. Because of their markings and silvery colour, banded archerfish are sometimes kept as aquarium fish, though they are difficult to care for and not recommended for most home aquaria.

 

Indo-Pacific region

Indo-Pacific region

 

Toxotes jaculatrix were originally described by Peter Simon Pallas in 1767. Since then, several synonyms (such as Labrus jaculatrix and Sciaena jaculatrix) and misspellings (Toxotes jaculator) have come into use.

Banded archerfish have four dorsal spines, 11 to 13 dorsal soft rays, three anal spines (of which the third is longest) and 15 to 17 anal soft rays. The first spine is always the shortest. The rays become shorter toward the posterior end. There are about 23 scales between the first dorsal spine and the posterior nostrils. Certain areas of the body are tinged green. The back of the fish is olive-green or brown. The dorsal fin is yellowish-green and located towards the posterior end, and its base is shorter than that of the anal fin. The caudal fin is “dirty green” and about the same height until the point of attachment, where it becomes shallower. The anal fin is silver.

The body of the banded archerfish is oblong in shape and raised on the posterior side. The body is generally silver-white in colour, though varying colourations, such as yellow, have been observed. Four to six broad black bars may be present on the dorsal side. The first bar is found anterior to the operculum, the bony plate covering the gills, and the second is found behind the operculum. The third bar is found below the origin of the dorsal fin, the fourth bar below the soft dorsal, and the fifth (if any) on the area between the anal fin and caudal fin (caudal peduncle). These bars become shorter as the fish ages. The lateral line curves upwards at the area between the fourth and ninth lateral scales. Banded archerfish can reach a maximum length of 30 centimetres (12 in), however, average length is about 20 centimetres (7.9 in).

The shooting behaviour of the banded archerfish is affected by the presence of conspecifics. When conspecifics are visible, this archerfish usually takes longer to shoot, aims more often, and shoots from a closer distance. This is hypothesized to occur to decrease the possibility of kleptoparasitism occurring.

Toxotes jaculatrix