Paedocypris progenetica

Paedocypris progenetica, the dwarf goby, is a species of tiny cyprinid fish endemic to the Indonesian islands of Sumatra and Bintan where it is found in peat swamps and blackwater streams. It was discovered by Singaporean ichthyologist Heok Hui Tan. He has written a description of the fish along with another species of the same genus called Paedocypris micromegethes.

It is one of the smallest known fish in the world, together with species such as Schindleria brevipinguis, with females reaching a maximum standard length of 10.3 mm, males 9.8 mm and the smallest known mature specimen, a female, measuring only 7.9 mm. It held the record for the shortest known vertebrate until the frog Paedophryne amauensis was formally described in January 2012, while the parasitic males of the anglerfish Photocorynus spiniceps are but 6.2 mm long.