Scientific name: Raphiodon vulpinus
Other names: Chafalote, machete, pez espada, pira yagua, dog fish, chambira – challua.
Weight and measures: Common average weight is 3 to 6 pounds, a big fish of this species reaches 80 inches long and weigh up to 9 pounds. However, there are records of fish of 1 meter in length and 11 pounds (5 kilograms). They usually reach large measures in terms of length rather than in their weight due to the appearance of their body.
Distribution: The basins of the Rio de la Plata, Paraná, Paraguay, Uruguay, the Amazon and Orinoco are the main fluvial systems where this specie can be found.
Habitat and life cycle: It is an extremely fast and elusive fish,
difficult to locate. It swims near the surface where it preys upon forage
It spawns in the months of January through March.
Appearance: It appears to be extremely fierce because of the two big teeth it has in the front of the lower jaw. They are prominent and sharp tusks that penetrate and settle into a sort of pod on the upper jaw. Consequently, there are few preys lucky enough to escape from their savage assaults.
Dog fish are big characins with deep, knife-shaped bodies and very large, upwards-pointing mouths. Their head is very small compared to its long and compressed body and their eyes are large in relation to the head. The jaw is prominent and narrow, with a wide mouth opening. Its color is silver and dark grey in the back.
Diet: It is an extremely voracious predator, piscivorous.