Some elements that had been referred to "Titanosaurus australis" were reassigned to "Laplatasaurus araukanicus" by Friedrich von Huene in 1929. The same year, von Huene named a "Titanosaurus robustus", and claimed it differed from "T. australis" in the limb material. Von Huene described all the slender limb material to "T. australis", but did not identify any differentiating features between the vertebrae. When describing "T. robustus", von Huene did not really compare other genera and species to it. From the syntype material assigned by von Huene to "T. robustus" José Fernando Bonaparte "et al." in 1978 chose four lectotypes, specimens MLP 26-250, MLP 26-252, MLP 26-254, and MLP 26-259, a left femur, both ulnae, and a left radius.