Monocirrhus polyacanthus

7. December 2010

The Leaffish, Monocirrhus polyacanthus, belongs to the most astonishing species of freshwater fish at all. The species – the genus Monocirrhus is monotypical – is spread all over the Amazon basin. It is found in Bolivia, Brazil, Colombia, Peru, and Venezuela. Our imports usually come from Peru, so the current one does.

The Leaffish belongs to the family Nandidae, which is a member of the perch-like order. Quite few genera and species are known, which come from tropical regions in Asia, Africa, and South America. This unusual distribution clearly shows that the nandids are an old family that existed already at a time when these three continents still formed a single land mass.

Most Leaffish are brownish and marbled. Both coloration and body shape imitate perfectly a dead leaf that is drifting in the water. This is the way the up to 12 cm long fish utilizes to come near to its prey: small, live fish, which form almost exclusively their diet. As soon as it is close enough, the Leaffish snaps with its bag-like, accordeon-shaped mouth and swallows the prey as a whole.

Our recent import contained some very pretty, brick-red specimens. Bright yellow Leaffish are also known. Nobody knows, if these colour morphs are restricted to special habitats or if any brood can contain a number of each colour morph. In any case the different coloration is no result of sexual dichromatism. Distinctive differences in the sexes are missing in Monocirrhus.

The Leaffish is a substrate spawner. The male takes care for the eggs until they hatch. In an aquarium, the Leaffish needs very clean, soft, and acidic water to thrive well. Only hobbyists that can guarantee the long term supply with small live feeder fish should keep these fascinating predators.

Lexicon: Monocirrhus: latin, means “with one thread”, referring to the fleshy barbel at the chin. polyacanthus: ancient Greek, means “with many spines”.

Common name: (South American) Leaffish

Text & Photos: Frank Schäfer

Angaben zum Tier
Herkunft Peru
Verfügbare Größe in cm 6-8