Scientists have discovered a fish living in forest swamps on the Indonesian island of Sumatra that is only 7.9 millimeters long.
The species of fish belongs to the carp family and is called Paedocypris progenetica . It is the world's smallest vertebrate or backboned animal.
Being a high level predator means that the giant snakehead eats many other fishes, amphibians and even small birds, but is not preyed upon by many other species. The giant snakehead is considered gregarious, with the young often following their mother closely. There have been reports of protective mother giant snakehead attacking men who have disturbed the snakehead's school of juveniles.The species has the ability to crawl onto land, where it can survive for up to four days.
In 2002 and 2003, three specimens were caught in Maryland, all believed to have been released pets. In 2003, a giant snakehead was caught in Rock River, Wisconsin. . Biologists were concerned that warmwater effluents could allow the tropical species to survive in the colder climate.
In 2008 , a specimenof C. micropeltes was caught by an angler while fishing for pike on the River Witham in Lincolnshire, England. It is not clear if the species is breeding in the wild, or if this was an escaped captive specimen; a source within the Environment Agency was quoted as saying “The reaction was, 'Oh s***'. This is the ultimate invasive species — if it starts breeding here it's a disaster."http://www.outdoorcentral.com/mc/pr/03/09/24c6.asp
Large sea spiders, jellyfish with 12-foot tentacles, huge sea snails and starfish the size of big food platters were found during a 50-day voyage, marine scientist Don Robertson said.
Cold temperatures, a small number of predators, high levels of oxygen in the sea water and even longevity could explain the size of some specimens, said Robertson, a scientist with NIWA.
Robertson added that of the 30,000 specimens collected, hundreds might turn out to be new species.
It was known that the fish, which became isolated from its northern cousins 30 million years ago, lives in life's slow lane, with extremely slow rates of growth, metabolism and swimming activity.
Now scientists have discovered that it can slow even these processes down in winter by entering a dormant state while sitting on the bottom.
The fish throws a seasonal "switch" between a high gear in which it maximises feeding and growth in summer and a low one where it maximises the energy used during the long, Antarctic winter.