[2] The population was discovered in the 1950s and assumed to be a form of Dudleya greenei, a plant also occurring on the island which is similar but larger and contains the same number of chromosomes.
[3][4] Reid Moran regarded it as Dudleya greenei forma nana in an unpublished description.
He failed to accurately place the collection number, collector, collection date, type specimen, or the location of a type specimen in a herbarium, which meant that Thompson's description did not constitute a valid publication according to the International Code of Botanical Nomenclature.
[5] In 1997, botanist Stephen W. McCabe gave the species a proper description as Dudleya gnoma.
The habit of the plants to grow on flat areas and in shallow soil is also similar to the subgenus Hasseanthus.
The overwhelming majority of the other characteristics, including the average petal altitude, broad leaf bases, and evergreen nature, does place it in subgenus Dudleya.
[5] In horticultural or lush, rainy conditions, D. gnoma may produce additional branches on the inflorescence.
Even the smallest flowering forms of Dudleya greenei are distinguished from D. gnoma, because they have blunter leaf apices and leaves that are oblong and more round in cross section.
[1] Though rare in the wild, this dudleya is kept in cultivation by gardeners and enthusiasts of succulents, and a cultivar called 'White Sprite' is popular.
[3][6] The cultivar was first introduced and named by Abbey Garden in the early 1970s from a plant of Dorothy Dunn, who in turn acquired her material from Reid Moran.
Supplemental watering in summer may damage or even kill the roots, and leads to often little or stunted growth.