G. sternicla was first described in 1758 by Carl von Linne. Its original name was Clupea sternicla. It seems that Linne grouped this fish with the clupeomorphs, such as the gizzard shad.
Perception Channels: tactile ; chemical
US Federal List: no special status
CITES: no special status
No adverse relationships with humans known.
This species is a popular aquarium fish. It has been in Europe since 1912, and in America since at least the 1930's (Hems 1983).
The hatchet fish has a diet which is composed primarilly of insects and larvae. They only feed near the surface of the water, so many terrestrial insects which they eat have fallen into the water. A large part of their diet consists of many winged insects, a large assortment of aquatic insects, and some zooplankton such as daphnia (Hems 1983).
Gasteropelecus sternicla is known to naturally occur in the Amazon river basin and most of its tributaries. Most of the scientific expeditions that have collected this particular species have done so in the far north of the Amazon river system (Hems 1983).
Distribution map of the range of G. sternicla from the NEODAT II Project.
Biogeographic Regions: neotropical (Native )
As stated earlier, G. sternicla lives in the Amazon river and most of its tributaries. Here the fish lives near the surface. It frequents well-vegetated areas near shore, but when schooled, will venture out into open water (Hems 1983).
Terrestrial Biomes: rainforest
Aquatic Biomes: rivers and streams
Female Gasteropelecus sternicla are known to reach a maximum length of about 49 millimeters (mm), while their male counterparts reach a maximum of about 42 mm. They have a compressed body with near circular pectoral and abdominal regions. This area of the its body contains a group of well-developed pectoral muscles that may make up 25% of the its body weight. The pectoral fins are upward-facing and wing-like. The dorsal fin is placed in a small dip in an otherwise straightened back near the caudal peduncle. The caudal fin is rather unremarkable in appearence and of normal size. The ventral fins are smaller than normal and rather insignificant. The anal fin has a long base and ends near the tail base (Hems 1983; Davenport 1994; Alkins-Koo 2000).
Other Physical Features: bilateral symmetry
Research has shown that Gasteropelecus sternicla only breed for a short period coinciding with the start of the rainy season. The eggs are laid by the female, then the male will swim near the eggs and release his sperm. It is not known if the female releases all of her eggs at once, or if they are deposited at different times during the breeding season. It is known however, that all of the eggs are developed at the same time in the ovaries. The unusal shape and body cavity size of the species may account for the fact that its brood size is generally smaller than other tropical fishes of its size. Females as small as 33mm, and males as small as 31 mm, were both found to have mature gonads (Alkins-Koo 2000).
The common hatchetfish or river hatchetfish (Gasteropelecus sternicla) is a tropical fish belonging to the freshwater hatchetfish family (Gasteropelecidae). Originating in South America in the Peruvian and middle Amazon, the Guianas and Venezuela, it grows to about 2.5 inches (6.5 cm). The fish gets its name from its relatively large protruding belly which resembles a hatchet. Hatchetfish will often jump out of the water when alarmed, propelled by their large, winglike pectoral fins. They also jump to catch small aerial insects.
The river hatchetfish is a schooling species best kept in groups of five or more that spends most of its time in the top-level of the water where it searches for food. These fish are peaceful towards other fishes, but frequently bicker among themselves. Typical lifespan in captivity is around five years, but can live longer. They come from streams in a tropical climate and prefer water at pH 6–7, a water hardness of up to 15.0 dGH, and an ideal temperature range of (23-27 °C (73-81 °F) . As carnivores, they will readily eat many types of small annelid worms, insects, and crustaceans, and they will also eat standard flake foods. They have a reputation for being greedy fish.
Because of their natural tendency to jump when alarmed, they may jump out of aquarium tanks. To prevent this, the top must either be completely sealed, or the water level lowered so the edges of the tank extend further upwards than the fish are capable of jumping. This is also less common with the addition of floating plants, to provide cover. It is also advised to keep them in a planted aquarium.
Cuyuni fish (Gasteropelecus sternicula) of Guyana The common hatchetfish or river hatchetfish (Gasteropelecus sternicla) is a tropical fish belonging to the freshwater hatchetfish family (Gasteropelecidae). Originating in South America in the Peruvian and middle Amazon, the Guianas and Venezuela, it grows to about 2.5 inches (6.5 cm). The fish gets its name from its relatively large protruding belly which resembles a hatchet. Hatchetfish will often jump out of the water when alarmed, propelled by their large, winglike pectoral fins. They also jump to catch small aerial insects.
