Two infraspecific taxa previously treated as varieties of Gilia polyantha Rydb. are recognized as belonging to Ipomopsis multiflora (Nuttall) V.E.Grant, which requires lectotypification. The new combinations, Ipomopsis multiflora (Nuttall) V.E.Grant subsp. brachysiphon (Wooton & Standley) Wilken, comb. & stat. nov. and subsp. whitingii (Kearney & Peebles) Wilken, comb. & stat. nov. are necessary for the treatment of Ipomopsis in a forthcoming volume of the Flora North America North of Mexico.

The following nomenclatural novelties are established in the genus Cylindropuntia: C. acanthocarpa subsp. ramosa (Peebles) M.A.Baker & Cloud-H., C. alcahes subsp. gigantensis (Rebman) Rebman; C. alcahes subsp. mcgillii (Rebman) Rebman; C. ganderi subsp. catavinensis (Rebman) Rebman; C. imbricata subsp. rosea (DC.) M.A.Baker; C. imbricata subsp. spinosior (Engelmann) M.A.Baker, Cloud-H. & Majure; C. imbricata subsp. spinotecta (Griffiths) M.A.Baker; C. thurberi subsp. versicolor (Engelmann ex J.M.Coulter) M.A.Baker; C. whipplei subsp. enodis (Peebles) M.A.Baker. A lectotype is designated for the name Opuntia whipplei var. enodis Peebles.

The Mediterranean species Lythrum junceum Banks & Sol. is newly reported from California, based on multiple records from southwestern Alameda County and adjacent Santa Clara County. Previous collections, dating to at least 1905, were misidentified as L. californicum Torr. & A.Gray, but differ in their sprawling habit, white-based petals, and purple-spotted hypanthia. Diagnostic features, invasive potential, and speculations on origin are addressed. In addition, two species of Lythrum described from California in 1889 are typified: a lectotype for L. adsurgens Greene and a neotype for L. sanfordii Greene. The possible role of hybridization in the establishment of L. hyssopifolia L. and other introduced species of Lythrum in California is also discussed.

Malacothamnus enigmaticus K.Morse & T.Chester (Malvaceae) is a new species endemic to the desert edge of the Peninsular Range in San Diego County, California, USA, from the San Ysidro Mountains in the north to the Laguna Mountains in the south. It is the only Malacothamnus species in its geographic range, which contains a unique habitat in San Diego County. Malacothamnus enigmaticus is morphologically distinct in many inflorescence characteristics from its two most similar species, M. densiflorus (S.Watson) Greene and M. fasciculatus (Nutt. ex. Torr. & A.Gray) Greene, which are also geographically closest to the new species. A Principal Components Analysis (PCA) of morphological features shows that M. enigmaticus is clearly distinct from both M. densiflorus and M. fasciculatus, and that all three species show the same level of separation from each other. Hence M. enigmaticus should be equally recognized at species rank. Malacothamnus enigmaticus and M. fasciculatus are both distinguished from M. densiflorus by their much-higher density of stellate stem hairs, and in most specimens by their shorter stellate hair rays and more numerous stellate hairs on the calyx. Malacothamnus enigmaticus is distinguished from M. fasciculatus by its longer calyx bracts, and generally by its wider stipular bracts. Malacothamnus enigmaticus is a rare species, known from just two ∼150 km² areas separated by a gap of ∼15 km, one in the Laguna Mountains and one in the Pinyon Ridge / Culp Valley / San Ysidro Mountain area. Due to its limited range and small populations, we propose a California Rare Plant Rank of 1B.3 for the species.