At present, no living organisms have been found to live forever, the theory is that if the cells are renewed and replaced very quickly (new cells are constantly replacing the old ones), then they can live forever. But presumably the size should also be very large.

Lobsters also have a life expectancy, the current longest-lived American lobster life expectancy of up to 40 years, growing to more than 30 pounds. Lobster growth at the same time the size of the body will grow indefinitely, and ultimately die of shelling difficulties, so we see all kinds of state of the lobster in fact may be in its young period, because it simply can not live "old age"