The fossils were collected by a team led by paleontologist William R. Hammer during a 1990–91 field expedition to the central region of the Transantarctic Mountains.

They come from sedimentary rocks of the Hanson Formation and date to the Pliensbachian stage of the Early Jurassic, around 186 to 182 million years ago.

Fossils of a sauropodomorph dinosaur were discovered by a field team from Augustana College led by paleontologist William R. Hammer during 1990–91 fieldwork in the lower Hanson Formation of Mount Kirkpatrick in the Central Transantarctic Mountains of Antarctica, dating to the Early Jurassic.

[3] The fossils were described by the paleontologists Nathan Smith and Diego Pol, who named the new genus and species Glacialisaurus hammeri, with FMNH PR1823 as holotype specimen.

[3] The diagnostic traits (characteristics that distinguish a taxon from others) of the second metatarsals include: a front border that is weakly convex in proximal aspect; a hypertrophied lateral plantar flange on the proximal end (present, but less developed in many basal sauropodomorphs, e.g., Saturnalia, Plateosaurus); and a medial distal condyle that is more robust and well−developed than the lateral distal condyle.

The hind edge is narrower from side toside than the front one, but is not acute or rounded, causing the upper outline of metatarsal III to be almost trapezoidal, as in Lufengosaurus, Gyposaurus, and Coloradisaurus.

[3] The phylogenetic position of Glacialisaurus is unstable due to its fragmentary nature, but it is frequently found to be a member of the family Massospondylidae.

[7][8][9][10][11][3] Massospondylids are a group of non-eusauropod sauropodomorphs that existed during the Late Triassic to Early Jurassic in Africa, Antarctica, Asia, and the Americas.

[3] Features of its foot are similar to Lufengosaurus (from the Early Jurassic of China), and the phylogenetic study suggested that these dinosaurs were close relatives, whereas Massospondylus was found to be a more basal form.

[3] This has been supported by later analyses,[12][8][9][10][7] including Müller (2019) which found it in a clade with Coloradisaurus and Lufengosaurus, while Massospondylus, Sarahsaurus, Pradhania, and Xingxiulong were more basal in the family.

The specimens were discovered in tuffaceous siltstone deposited in the Sinemurian to Pliensbachian stage of the Early Jurassic,[2][14] dating to about 194–188 million years ago.

[14] The high altitude of this site supports the idea that early Jurassic Antarctica had forests populated by a diverse range of species, at least along the coast.

[16] This formation has yielded the remains of the large theropod Cryolophosaurus, a crow-sized dimorphodontid pterosaur, a rat-sized tritylodont synapsid, and two small unnamed sauropodomorphs.

[15][3][4] Many plant genera have also been recovered from the Shafer Peak section of the Hanson Formation that suggest forests similar to the open woodlands of North Island, New Zealand.