[1] The genus name of Johnstonella is in honour of Ivan Murray Johnston (1898–1960), an American botanist.

[1] Then in 1927, Ivan M. Johnston wrote that the genus of Oreocarya (in the Boraginaceae family) could be combined with Cryptantha.

Then Edwin Blake Payson in 1927 (A Monograph of the section Oreocarya of Cryptantha, Ann.

Larry Higgins (1971), another expert on the perennial taxa, published a revised monograph of Oreocarya, and agreed with Johnston and Payson on the inclusion of Oreocarya within Cryptantha, but also elevating the four sections of Johnston (1927) and Payson (1927) to subgenera.

[4] In 2012, the phylogenetic relationship of members of the genus Cryptantha was carried out, based on dna sequencing analyses, it was then proposed that the resurrection of the following genera Eremocarya, Greeneocharis, Johnstonella, and also Oreocarya.