Largest organisms one of the largest and oldest clonal colonies on Earth. Among animals, the largest species are all marine mammals, specifically whales. The blue whale is believed to be the largest animal to have ever lived. The largest land animal classification is also dominated by mammals, with the African bush elephant being the most massive of these. The largest single-stem tree by wood volume and mass is the giant sequoia ("Sequoiadendron giganteum"), native to Sierra Nevada and California; it typically grows to a height of and in diameter. Multiple-stem trees such as banyan can be enormous. Thimmamma Marrimanu in India spreads
Animal measuring up to long. The largest terrestrial animals that ever lived were titanosaur sauropod dinosaurs such as "Argentinosaurus", which may have weighed as much as 73 tonnes. Several animals are microscopic; some Myxozoa (obligate parasites within the Cnidaria) never grow larger than 20 µm, and one of the smallest species ("Myxobolus shekel") is no more than 8.5 µm when fully grown. The following table lists estimated numbers of described extant species for the animal groups with the largest numbers of species, along with their principal habitats (terrestrial, fresh water, and marine), and free-living or parasitic ways of life. Species estimates