Lupinus argenteus Pursh var. tenellus (Douglas ex G. Don) D.B. Dunn × Lupinus caudatus Kellogg
Annotated by David B. Dunn, Jan 1955. Remarks: "Lupinus caudatus x L. argenteus var. tenellus. Has the vegetative traits of the former as well as ciliation above the claws of the wings and keel, and densely cileate keel. But has the small flowers of the latter. D.B. Dunn, Jan 1955".

Idaho: Bingham County: East [of] Fort Hall. Elev. 4500 ft.
43.033248° N, 112.438313° W,
Datum: WGS 84. Uncertainty: 8700 meters. Coordinate Source: Digital Map.
Dry soil among sage brush. Holotype. Phenology: Flowers & Fruits. Type specimen (basionym and designation not recorded).

Ray J. Davis 137-35, Jul 5, 1935
IDS, Accession: 1994.051, Catalog: 1994.51.25, Barcode: IDS0057568