Allenbya collinsonae is known exclusively from the Princeton Chert, a fossil locality in British Columbia, Canada,[2] that contains an anatomically preserved flora of Eocene Epoch age, with rich species abundance and diversity.

The chert is located in exposures of the Allenby Formation on the east bank of the Similkameen River, 8.5 km (5.3 mi) south of the town of Princeton, British Columbia.

The highlands temperate biome preserved across a large transect of lakes recorded many of the earliest appearances of modern genera, while also documenting the last stands of ancient lines.

[5] The fossils were first studied by Sergio R. S. Cevallos-Ferriz and Ruth A. Stockey in the late 1980s who used cellulose acetate peels with hydrofluoric acid to create serial thin sections of the chert blocks.

[2][7] At the time of description A. collinsonae was placed in the family Nymphaeaceae,[8] and was suggested by Cevallos-Ferriz and Stockey to be an early member of the linage leading to the modern giant waterlily[9] genus Victoria.

[10][9] Allenbya collinsonae seeds are noted to be bigger than those of the related Susiea newsalemae from the Paleocene Sentinel Butte Formation of Almont, North Dakota, which are also more barrel-shaped.

The three genera are closely related "hyphomycetes" making determination of the fossils affiliation hard, but based on the sclerotium, mycelium, and phragmospores, LePage et al considered it most similar to the living Alternaria padwickii.

[4] The Okanagan Highland sites, such as the Princeton chert represent upland lake systems that were surrounded by a warm temperate ecosystem with nearby volcanism.

[5] The highlands likely had a mesic upper microthermal to lower mesothermal climate, in which winter temperatures rarely dropped low enough for snow and which were seasonably equitable.

[13] The warm temperate uplands floras of the Allenby Formation and greater highlands in association with downfaulted lacustrine basins and active volcanism are noted to have no exact modern equivalents.