Halmaturus Greyi (now known as Macropus Greyi) was named after the explorer and South Australian Governor, Sir George Grey. Grey led an expedition to the South East of South Australia in 1844. It is possible this specimen was collected on that journey; it was described by GR Waterhouse in his 1848 publication A natural history of the mammalia. John Gould included two lithographs of it in his three volume folio The Mammals of Australia. He writes:

'This fine wallaby was first sent to this country [i.e.England] from South Australia by His Excellency Sir George Grey after whom it was named. It is a species quite distinct from every other, but is perhaps most nearly allied to the Halmaturus manicatus, an animal inhabiting the country farther to the westward ... Its favourite places of rest are flats near the sea-shore, particularly low sand-hills and open grounds, where the surface is bare and unbroken ...'

The specimen was caught between Lake Albert and the Glenelg River.