Brontosaurus
"Brontosaurus" was a large, long-necked quadrupedal animal with a long, whip-like tail, and forelimbs that were slightly shorter than its hindlimbs. The largest species, "B. excelsus", weighed up to and measured up to long from head to tail. For comparison, the current largest land animal, the average male African bush elephant is 3.20 m (10.5 ft) tall at the shoulder and has a body mass of 6,000 kg (13,228 lb) or 6.6 short tons.
Neosauropoda
Macronaria is defined as all neosauropods more closely related to "Saltasaurus loricatus" than "Diplodocus longus". This classification was introduced by Wilson and Sereno in 1998. Macronaria comes from the Latin for “large nose,” referring to the large external naris. The subgroup Titanosauriformes comprises all sauropods descended from the common ancestor of "Brachiosaurus" and "Saltasaurus". Macronaria is an exceedingly diverse clade, with members ranging in size from anywhere between six and thirty-five meters in length and sporting a broad array of body shapes. Some synapomorphies which have been used to characterize macronarians include flared neural spines on the dorsal vertebrae and nearly coplanar ischial distal shafts.