which animal has the longest lifespan?

The longest-lived animals are deep-sea glass sponges, with some estimated to be over 15,000 years old, followed by black corals at around 4,200 years and the immortal jellyfish, which can revert to a younger state and live indefinitely. Other long-lived creatures include the ocean quahog clam (over 500 years), the Greenland shark (over 400 years), and the bowhead whale (over 200 years).

some of the Giant tortoises on those islands get really old

There is a basking shark supposedly over 109 yrs old

There are Greenland sharks that are older than the USA.