http://news.bbc.co.uk/2/hi/sci/tech/4645708.stm

Scientists find ‘smallest fish’

Scientists have discovered the smallest known fish on record in the peat swamps of the Indonesian island of Sumatra.

Mature individuals of the Paedocypris genus can be as small as 7.9mm (0.3in) long! To keep their size down, the fish have abandoned many of the attributes of adulthood – a characteristic hinted at in their name. Being so small, the fish can live through even extreme drought, by seeking refuge in the last puddles of the swamp.

Scientists warn long-term prospects for the fish are poor, because widespread forest destruction, drainage of the peat swamps for palm oil plantations and persistent fires are destroying their habitat.