geoduck

The Pacific geoduck ( ; Panopea generosa) is a species of very large saltwater clam in the family Hiatellidae. The common name is derived from the Lushootseed name, .

The geoduck is native to the coastal waters of the eastern North Pacific Ocean from Alaska to Baja California. The shell of the clam ranges from to over in length, but the extremely long siphons make the clam itself much longer than this: the "shaft" or siphons alone can be in length. The geoduck is the largest burrowing clam in the world. It is also one of the longest-living animals of any type, with a typical lifespan of 140 years; the oldest has been recorded at 179 years old. The precise longevity of geoducks can be determined from annual rings deposited in the shell which can be assigned to calendar years of formation through crossdating. These annual rings also serve as an archive of past marine variability. thumb|Geoduck growth increments