field guide to the freshwater fishes of singapore

Index of fishes
General parts of a fish
Kelvin K P Lim and Peter K L Ng
  Fishy Facts
Some amazing fishes | More amazing fishes

diagram of african lungfish
African Lungfish
The African Lungfishes (Protopterus, Protopteridae) build themselves a "cocoon" of mud beneath the bottoms of dried up ponds and have been known to aestivate ("sleep") for as long as four years!

Some freshwater fishes naturally swim upside down. Most famous is the West African Upside Down Catfish (Synodontis nigriventris, Synodontidae). They are so well adapted to this lifestyle that the normal colour pattern is reversed - the ventral surfaces being darkly coloured whereas the dorsal areas are light coloured.
photo of whole fish, side view
Upside Down Catfish
Photo: Francis Lim
photo of whole fish, side view
Photo: Francis Lim
The most dangerous freshwater fishes in the world are probably the various species of South American Piranha (Serrasalmus, Characidae), distant relatives of the famous aquarium tetras.
diagram of piranha jawsThey are especially dangerous in schools, their sharp teeth easily slicing off the flesh. Attracted by blood, they have been known to strip a human to his skeleton in several hours. They are unpredictable animals, however, and do not usually attack man. Because of their ferocity, they are banned from the aquarium trade in many countries. In Singapore, specimens have been occasionally reported to be released in drains. They are not known to be feral. It is illegal to keep or sell them here. Just imagine our reservoirs and waterways teeming with them!

The most "electrifying" of all fishes is the freshwater South American Electric Eel, (Electrophorus electricus, Electrophoridae), which can generate up to 600 volts of charge at currents of up to 1 ampere. Deaths are rare. Second in line is the African Electric Catfish (Malapterurus electricus, Malapteruridae) which can generate over 250 volts. This fish has been known since the time of the Pharaohs.
diagram of electric catfish
Electric catfish

diagram of electric eel
Electric Eel

close-up of lips of kissing fish
Kissing Fish
Photo: Tan Bee Hong
Kissing fishes or Kissing Gouramies (Helostoma temminckii, Helostomatidae) "kiss" by oppressing their fleshy lips against each other, but it is believed that this action is not one of affection but a threat display between rivals!

photo of whole fish, from aboveOne of the prime contenders for the ugliest freshwater fish in the world must surely be the Angler Catfish of Malaysia (Chaca bankanensis, Chacidae). Not only does it not look like any living thing, it uses the two worm-like barbels to lure small fishes to its huge mouth!

cartoon of air-breathing fishSurprising as it may sound, some fish can drown if forced to stay under water too long! All have special body structures adapted to breathe air, particularly the labyrinth fishes (Belontidae, Anabantidae, etc). These are so dependent on atmospheric air that their gills are small and very ineffective under water. If forced to stay underwater for too long, they literally drown! South East Asia has one of the highest concentration of such air-breathing fishes in the world.
Freshwater habitats
Fishes in Singapore
Amazing Fishy Facts
About the guidebook
From A Guide to Common Freshwater Fishes of Singapore by Kelvin K P Lim and Peter K L Ng
Published by the Singapore Science Centre and sponsored by BP

@Raffles Museum of Biodiversity Research and Singapore Science Centre