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

In this general section, we have compiled some amazing and sometimes little known facts about freshwater fish. We have included freshwater fishes from around the world to make it more interesting.

diagram of danionella

diagram of pandaka
In 1986, an American ichthyologist recorded the Burmese cyprinid Danionella translucida as the smallest freshwater fish, females being mature at only 10 to 1 lmm in standard length.

Prior to this, the smallest freshwater fish was the goby Pandaka pygmaea from the Philippines which can grow a few millimetres larger and is much stouter.

There are several candidates for the largest freshwater fish in the world. The South American Arapaima or Pirarucu (Arapaima gigas, Osteoglossidae) is a prime contender at reported lengths of 4.5m, and weighing 200 kg. The largest known specimen of the Giant European Catfish, or Wels (Silurus glanis, Siluridae) reached 5 m in length and over 300 kg. The euryhaline Russian sturgeons (Acipenseridae) Beluga (Huso huso) (not to be confused with the white whale which bears the same name) and Kaluga (Huso dauricus) easily reach 5 m in length, and can weigh an astonishing 1500 kg!
diagram of arapaima

diagram of wels

diagram of beluga
diagram of mekong catfish
Mekong Catfish
The giant Mekong Catfish (Pangasianodon gigas, Pangasiidae) which lives in the Mekong River, easily reaches 2.5 metres in length and is an important food resource, having being successfully cultured by the Thais.
This peaceful giant is known locally as Pla Buk or "Huge Fish". Young fishes have teeth and barbels, lacking in adults.

diagram of candiru
A very slender and small 2.5 cm catfish called the Candiru (Vandellia cirrhosa, Trichomycteridae) from the Amazon
has the nasty reputation of entering the urethra of people urinating under water! Once inside, their spiny gill covers make them impossible to extract except by surgery. They normally feed on the gill tissues of fishes.

The predatory Giant Malayan Catfish or Tapah (Wallago leerii, Siluridae) of South East Asia which can reach 2 m in length, has such a huge gape (mouth width) that it has been reported to swallow small dogs and mousedeer!
photo of tapah
Photo: Francis Lim
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