BANGKOK, Thailand — Scientists say they have discovered the
world's smallest known fish in threatened swampland in Indonesia.
The fish, a member of the carp family, has a translucent body
and a head unprotected by a skeleton.
Mature females grow to less than a third of an inch long. The
males have enlarged pelvic fins and muscles that may be used in
reproduction, researchers wrote in a report published Wednesday by
the Royal Society in London.
"This is one of the strangest fish that I've seen in my whole
career," said Ralf Britz, a zoologist at the Natural History Museum
in London. "It's tiny, it lives in acid and it has these bizarre
grasping fins. I hope we'll have time to find out more about them
before their habitat disappears completely."
The fish are found in an acidic peat swamp on the Indonesian
island of Sumatra. Indonesian peat swamps are under threat from
fires lit by plantation owners and farmers as well as unchecked
development and farming. Researchers say several populations of the
tiny fish, Paedocypris progenetica, have already been lost,
according to the Natural History Museum.
The previous record for world's smallest fish, according to the
Natural History Museum, was held by a species of Indo-Pacific goby
one-tenth of a millimeter longer.
"You don't wake up in the morning and think, 'Today we will
find the smallest fish in the world,"' Swiss fish expert Maurice
Kottelat, who helped discover the fish, said in a telephone
interview from his home in Switzerland.
According to researchers, the little fish live in dark,
tea-colored water at least 100 times more acidic than rainwater.
Such acidic swamps was once thought to harbor few animals, but
recent research has revealed that they are highly diverse and home
to many unique species.