Phylogenetic studies starting with Pires and Sytsma in 2002 indicated that the genus Dichelostemma was not monophyletic. Specifically, Dichelostemma capitatum (Blue Dicks) is genetically a sister to the clade that includes all the Brodiaea species and the other four species of Dichelostemma. Botanists studying floral morphology had reached a similar conclusion.

Robert Preston resolved this in the 2017 paper referenced below by restoring the genus Dipterostemon (originally created by Rydberg in 1912) and moving Blue Dicks into it under the name Dipterostemon capitatus. The Jepson eFlora has accepted this change: https://ucjeps.berkeley.edu/eflora/eflora_display.php?tid=108599, but it hasn't yet been picked up by Plants of the World Online: http://plantsoftheworldonline.org/taxon/urn:lsid:ipni.org:names:82063-2

I will manually create taxonomic changes for the subspecies because the rules of Latin gender mean that the nominate subspecies name will change its final letter.

• "New nomenclatural combinations for blue dicks (Dipterostemon capitatus; Asparagaceae: Brodiaeoideae)." Preston, 2017, http://www.phytoneuron.net/2017Phytoneuron/15PhytoN-Dipterostemon.pdf