Sauroposeidon
The press release in 1999 immediately garnered international media attention, which led to many (inaccurate) news reports of "the largest dinosaur ever!". While "Sauroposeidon" likely represents the tallest known dinosaur taxon, it does not hold records for either the longest or most massive. "Patagotitan" or "Argentinosaurus" make better candidates for the title "World's Largest Dinosaur" (presuming to ignore, as is conventional, "Amphicoelias"), though incomplete fossil evidence makes exact rankings impossible.
Antarctosaurus
Antarctosaurus (; meaning "southern lizard") is a genus of titanosaurian sauropod dinosaur from the Late Cretaceous Period of what is now South America. The type species, "Antarctosaurus wichmannianus", was described by prolific German paleontologist Friedrich von Huene in 1929, who also described a second species in 1929. Three additional species of "Antarctosaurus" have been named since then but later studies have indicated that none of these pertain to "Antarctosaurus. Antarctosaurus giganteus," the second species, is also considered dubious but it's remains represent one of the largest dinosaurs known.