The species is solely known from the early Eocene, Ypresian stage,[1] Allenby Formation Lacustrine deposits near the town of Princeton, British Columbia.

[2] The species was described from the two leaf specimens found at the One Mile Creek locality, UWBM number 53355 in 1991 by Wesley Wehr and Peter Dunthorne.

[2] Melanie DeVore and coauthors chose the specific name dunthornei, in honor of Peter Dunthorne of Sedro-Woolley, Washington in recognition of the collecting work throughout the Okanagan highlands which he helped and participated with.

Together the two compression-impression fossil leaves, preserved in light green-grey shale display the leaf shape, margin, and morphology of the vein structure and teeth.

[2] The presence of Neviusia in the Eocene Okanogan Highlands floras suggests the tribe Kerrieae originated in Asia and radiated to North America but did not become a major floristic component.