What are the longest-living organisms on Earth?

The answer

The oldest individual non-clonal organism is a Great Basin bristlecone pine named Methuselah, located in California's White Mountains, aged over 4,850 years. The oldest known clonal organism is a Posidonia oceanica seagrass meadow in the Mediterranean estimated at 100,000 years old. Among animals, the ocean quahog clam 'Ming' was 507 years old when harvested. Greenland sharks can live over 400 years, not reaching sexual maturity until around age 150. Some sponges in the Antarctic are estimated at over 10,000 years old. At the microbial level, bacteria have been revived from 250-million-year-old salt crystals, though whether they were truly alive during that time remains debated.