Recent morphological and phylogenetic analyses show M. helleri to be distinct from the rest of M. fremontii but nested within the M. fremontii clade with some less clear lineages. Because of this, the 2023 Malacothamnus treatment recognizes M. helleri as a variety of M. fremontii and, due to taxonomic priority, is given the name M. fremontii var. exfibulosus. To be consistent with M. fremontii var. fremontii (long-haired unfurled bushmallow), the common name short-haired unfurled bushmallow is the suggested common name in the 2023 treatment. The short-haired part of the common name refers to the length of stem hairs that distinguish the two varieties. The name unfurled bushmallow is the suggested alternative for Fremont's bushmallow for those who do not want to honor someone responsible for multiple massacres of Indigenous people. Unfurled refers to the state of the corolla after flowering. In most Malacothamnus taxa, the corolla furls back up after flowering. In M. fremontii, it stays at least somewhat unfurled. This is the most useful character for identifying M. fremontii. More details in the new treatment here:
https://doi.org/10.6084/m9.figshare.23937066