The World’s Smallest Fish

They are small, they are tiny, they are fish, and they are weird. The World’s smallest fish are the Paedocypris progenetica of the carp family which measure less than 8mm in size and live in swamps with a pH of 3.

They measure 7.9mm:
They are small, they are rare and they are weird! Imagine fish that measure less than a centimeter, 7.9 millimeters to be exact. They are the smallest fish in the world and inhabit acidic water with a PH of 3, 100 times more acidic than rain water. They have grasping fins and dwell in threatened swamps.




They were discovered in 2006 in Sumatra, Indonesia:
Scientists discovered these tiny fish in 2006 in forest swamps on the Indonesian island of Sumatra. They belong to the carp family and have been named Paedocypris progenetica. Several populations of these tiny fish have already been lost due to forest fires that decimated their habitats.



They have a reduced head skeleton with larvae like appearance
The fish are tiny see through vertebrates that have a larvae appearance and a reduced head skeleton leaving their brains without bone protection. Aside from being the world’s smallest fish, the Paedocypris progenetica holds the record for being the world’s smallest vertebrate after eclipsing the previous record of 8mm held by an Indo pacific goby.




Discovered by ichthyologists:
The fish were discovered by fish experts Maurice Kottelat from Switzerland and Tan Heok Hui from the Raffles Museum of Biodiversity Research in Singapore. They were working with their colleagues from Indonesia and with Kai-Erik Witte from the Max Planck Institute in Germany.