ScienceDaily (Oct. 29, 2007) — A clam dredged from Icelandic waters had lived for 400 years - is this the longest-lived animal known to science?

Can you imagine living for four centuries?  A team of scientists from Bangor University's School of Ocean Sciences believe they have found an animal which did just that, a quahog clam, Arctica islandica, which was living and growing on the seabed in the cold waters off the north coast of Iceland for around 400 years. 

According to the Guinness Book of Records, the existing record for the longest-lived animal belongs to a 220 year old Arctica clam collected in 1982 from American waters.  Unofficially, the record belongs to a 374 year old Icelandic clam which was found in a museum.  Both these records appear to have been eclipsed by the latest specimen, whose age, between 405 and 410 years, has been assessed by counting the annual growth lines in the shell.