baluchitherium, extinct primitive rhinoceros, belonging to the genus Baluchitherium, of the Oligocene epoch, fossilized bones of which were found in central Asia. It had an estimated shoulder height of nearly 18 ft (5.5 m) and a weight of about 10 tons, and is believed to have been the largest land mammal of all time. The baluchitherium is classified in the phylum Chordata, subphylum Vertebrata, class Mammalia, order Perissodactyla, family Rhinocerotidae.