Freshwater
Longtail knifefish
Sternopygus macrurus
Sternopygidae
Facts
Characteristics
- Length
- Up to 140.5 cm
- Body shape
- Elongated
Care
- Group
- Missing
- Smallest aquarium
- 58,400 liters
- Diet
- Missing
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Behavior
Water values
Smallest tank
Range
Native
Lives wild in Argentina, Bolivia, Brazil, Colombia, Ecuador, French Guiana, Guyana, Paraguay, and 3 more countries.
More about the species
Description
Occurs in swamps, creeks, and river with lentic waters. Preys on small invertebrates, particularly the larvae of aquatic insects. Breeds before the start of the rainy season or during the rainy season, with a fecundity count of 6473 eggs. Males persistently defend their territory and apparently make electric signals (by increased electric organ discharge (EOD) rates and interruptions thereof) to females passing by to draw in a spawning partner. Mature females' EODs are of higher frequencies than mature males. Plasma androgens modulate the EOD frequency during the breeding season. Embryos hatch on day 4; larvae begin to feed on day 11. The electric organ and electroreceptors are both present in the larva at the time of first exogenous feeding. Seems to reach sexual maturity at 1 year of age, based on breeding experiments.
Other names
Other scientific names
- Carapus sanguinolentus
- Gymnotus macrurus
- Hildatia brasiliensis
- Sternopygus marcgravii
- Sternopygus obtusirostris
In other languages
- Siimaveitsikala
Articles
All articles
Fish that get along4 min read
Temperament, fin nippers, fish that eat other fish, and fish that need the same water. And what the Harmony mark in the app means.
How to set up a South American aquarium4 min read
Soft, acidic water, subdued light, sand, roots and fallen leaves: how to set up a biotope aquarium from the Amazon and the rivers around it.
How to add new fish4 min read
From the store to the tank: how to get the fish used to your water, why you should add only a few at a time, and what to watch for in the first few days.
Quarantine for new fish3 min read
Why new fish should live in a tank of their own for a few weeks before they move in, what you need, and what to look for.