Smallscale archerfish
Encyclopedia
The smallscale archerfish (Toxotes microlepis) is a perciform fish of genus Toxotes
. As its name suggests, the scales of the smallscale archerfish are smaller than those of other archerfish. They reach a maximum length of 15 centimetres (5.9 in). Smallscale archerfish live in the tropical Indo-Pacific region and are potamodromous, moving between fresh and brackish water through their lifetimes.
, with four to five dorsal spine
s. The fourth spine is longer than the third. The second dorsal spine is slightly shorter than the third anal spine, which itself is shorter than the soft rays. There are usually 40 to 42 lateral line
scales, though some specimens found in the Mekong had 34 to 37. The species T. blythii
was formerly thought to be identical to T. microlepis. Differences in structure and colouration caused the splitting of T. blythii into a new species.
Like other archerfish, they have dark, wedge-shaped bands or spots on its flanks, which can be yellow to silvery. They reach a maximum length of 15 centimetres (5.9 in) in the wild, and 12 centimetres (4.7 in) in captivity. The smallscale archerfish is sometimes confused with the banded archerfish
, T. jaculatrix. Both species have four or five wedge-shaped bars on their flanks. However, the bars of banded archerfish extend to the dorsal fin
whilst those of the smallscale archerfish do not; they stop below the dorsal fin, with another dark spot on the fin itself. The smallscale is also has a shorter snout than other archerfish.
, crustaceans, and insect larvae.
in Asia and the Indo-Pacific. They are distributed throughout the Mekong
and Chao Phraya river basins as well as waters off the Malay Peninsula
, Sumatra
and Borneo
. They can be found near the shores of moving and standing waters, usually with overhanging plants. The smallscale archerfish is described as a "freshwater archerfish", as it does not move into saltwater during its life as do some other archerfish. It is found upstream from the estuary more often than other species of the genus.
. It is often confused with other archerfish (such as the banded archerfish
and largescale archerfish
), and may be sold with the others as one species. Smallscale archerfish do not need brackish water as do other members of its genus (though it can also live in brackish water); it is thus sometimes sold as the "freshwater archerfish".
Archerfish
The archerfish are a family of fish known for their habit of preying on land based insects and other small animals by literally shooting them down with water droplets from their specialized mouths...
. As its name suggests, the scales of the smallscale archerfish are smaller than those of other archerfish. They reach a maximum length of 15 centimetres (5.9 in). Smallscale archerfish live in the tropical Indo-Pacific region and are potamodromous, moving between fresh and brackish water through their lifetimes.
Description
Smallscale archerfish have a pointed snout and large eyes. The back is flat and the belly is curved. There is only one dorsal finDorsal fin
A dorsal fin is a fin located on the backs of various unrelated marine and freshwater vertebrates, including most fishes, marine mammals , and the ichthyosaurs...
, with four to five dorsal spine
Fish anatomy
Fish anatomy is primarily governed by the physical characteristics of water, which is much denser than air, holds a relatively small amount of dissolved oxygen, and absorbs more light than air does.- Body :...
s. The fourth spine is longer than the third. The second dorsal spine is slightly shorter than the third anal spine, which itself is shorter than the soft rays. There are usually 40 to 42 lateral line
Lateral line
The lateral line is a sense organ in aquatic organisms , used to detect movement and vibration in the surrounding water. Lateral lines are usually visible as faint lines running lengthwise down each side, from the vicinity of the gill covers to the base of the tail...
scales, though some specimens found in the Mekong had 34 to 37. The species T. blythii
Toxotes blythii
Toxotes blythii is a perciform fish of genus Toxotes. It is amphidromous and found in Myanmar. T. blythii is not of interest in fisheries. This species was formerly thought to be identical to T. microlepis . However, differences in structure and colouration caused the splitting of T. blythii into...
was formerly thought to be identical to T. microlepis. Differences in structure and colouration caused the splitting of T. blythii into a new species.
Like other archerfish, they have dark, wedge-shaped bands or spots on its flanks, which can be yellow to silvery. They reach a maximum length of 15 centimetres (5.9 in) in the wild, and 12 centimetres (4.7 in) in captivity. The smallscale archerfish is sometimes confused with the banded archerfish
Banded archerfish
The banded archerfish 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"...
, T. jaculatrix. Both species have four or five wedge-shaped bars on their flanks. However, the bars of banded archerfish extend to the dorsal fin
Dorsal fin
A dorsal fin is a fin located on the backs of various unrelated marine and freshwater vertebrates, including most fishes, marine mammals , and the ichthyosaurs...
whilst those of the smallscale archerfish do not; they stop below the dorsal fin, with another dark spot on the fin itself. The smallscale is also has a shorter snout than other archerfish.
Diet
Smallscale archerfish eat terrestrial insects (which they can shoot down), zooplanktonZooplankton
Zooplankton are heterotrophic plankton. Plankton are organisms drifting in oceans, seas, and bodies of fresh water. The word "zooplankton" is derived from the Greek zoon , meaning "animal", and , meaning "wanderer" or "drifter"...
, crustaceans, and insect larvae.
Distribution and habitat
Smallscale archerfish inhabit large rivers and estuariesEstuary
An estuary is a partly enclosed coastal body of water with one or more rivers or streams flowing into it, and with a free connection to the open sea....
in Asia and the Indo-Pacific. They are distributed throughout the Mekong
Mekong
The Mekong is a river that runs through China, Burma, Laos, Thailand, Cambodia and Vietnam. It is the world's 10th-longest river and the 7th-longest in Asia. Its estimated length is , and it drains an area of , discharging of water annually....
and Chao Phraya river basins as well as waters off the Malay Peninsula
Malay Peninsula
The Malay Peninsula or Thai-Malay Peninsula is a peninsula in Southeast Asia. The land mass runs approximately north-south and, at its terminus, is the southern-most point of the Asian mainland...
, Sumatra
Sumatra
Sumatra is an island in western Indonesia, westernmost of the Sunda Islands. It is the largest island entirely in Indonesia , and the sixth largest island in the world at 473,481 km2 with a population of 50,365,538...
and Borneo
Borneo
Borneo is the third largest island in the world and is located north of Java Island, Indonesia, at the geographic centre of Maritime Southeast Asia....
. They can be found near the shores of moving and standing waters, usually with overhanging plants. The smallscale archerfish is described as a "freshwater archerfish", as it does not move into saltwater during its life as do some other archerfish. It is found upstream from the estuary more often than other species of the genus.
Relationship to humans
Some aquarists believe the smallscale archerfish is the most frequently traded archerfishArcherfish
The archerfish are a family of fish known for their habit of preying on land based insects and other small animals by literally shooting them down with water droplets from their specialized mouths...
. It is often confused with other archerfish (such as the banded archerfish
Banded archerfish
The banded archerfish 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"...
and largescale archerfish
Toxotes chatareus
Toxotes chatareus, sometimes known by the common names seven-spot archerfish or largescale archerfish, is a species of perciform fish in the archerfish genus Toxotes. They are usually no larger than but may grow up to . Unlike most archerfish, T. chatareus are sooty rather than silvery in...
), and may be sold with the others as one species. Smallscale archerfish do not need brackish water as do other members of its genus (though it can also live in brackish water); it is thus sometimes sold as the "freshwater archerfish".