http://www.businessinsider.com/this-clam-was-alive-for-more-than-500-years-2013-11
I wish some enlightened billionaire would fund more studies of these "ageless animals". Evolution could tell us how to stop aging almost completely. The knowledge is out there, in their biochemistry. Most of them (or all, if you count tortoises) are aquatic. There's a clue there, somewhere.
metatron