The range of Malacothamnus hallii is adjacent to M. arcuatus s.s with morphological intermediates where their ranges meet. Phylogenetic analyses place both taxa in the same clade with some analyses indicating some divergence. While future research may show that M. arcuatus and M. hallii should be treated as two species, the 2023 treatment treats M. hallii as M. arcuatus var. elmeri, the elmeri part having taxonomic priority over hallii when treated as a variety. Placing both taxa in the same species allows intermediates to be classified to the species rank.

The suggested common name in the 2023 treatment for M. arcuatus at the species rank (s.l.) is bewildering bushmallow, which alludes to the taxonomic problems from the 2012 Jepson treatment where the author identified specimens of M. arcuatus s.s. as an amazingly large number of other species, presumably as M. arcuatus confounded her analyses. The common names of each variety adds their geographic placement relative to each other. M. arcuatus var. arcuatus is western bewildering bushmallow. M. arcuatus var. elmeri is eastern bewildering bushmallow.

See more details in my new treatment of Malacothamnus, which you can download for free here.

Recent morphological and phylogenetic analyses show M. helleri to be distinct 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, it is given the name M. fremontii var. exfibulosus. The rest of M. fremontii is now M. fremontii var. fremontii.

The common 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. The length of hairs on the stem is the easiest way to distinguish the M. fremontii varieties beyond geographic range. Thus, in the new treatment I suggest long-haired unfurled bushmallow for M. fremontii var. fremontii and short-haired unfurled bushmallow for M. fremontii var. exfibulosus.

At present, I have not changed the default common name for M. fremontii when no variety is used. If you have an opinion about whether the default should be changed to unfurled bushmallow or whether iNat should keep honoring Fremont, feel free to speak your mind. Both names will remain on iNat and come up in a search no matter which is set as the default.

See more details in my new treatment of Malacothamnus, which you can download for free here.

I've made a few changes to Malacothamnus jonesii, M. gracilis, and M. niveus on iNat.

Malacothamnus gracilis and niveus are sometimes treated as synonyms of M. jonesii without varieties. Morphological, phylogenetic, and geographic evidence indicates M. niveus and M.gracilis are likely best treated as a variety of M. jonesii. They are closely related and intergrade but are mostly morphologically and geographically distinct. The cool thing about treating them as varieties of M. jonesii is that it means I get to be a splitter and a lumper for the same taxa at the same time. It also means that intermediates can be easily IDed to just the species.

In the new treatment, I'm using the common name Huasna bushmallow for M. jonesii var. gracilis and fragrant-snow bushmallow for M. jonesii var. niveus. The Huasna region is the type locality for M. jonesii var. gracilis, so a much more useful name than slender bushmallow, which makes little sense relative to other Malacothamnus. Slender what and why? The original basionym of M. jonesii var. niveus was Malvastrum fragrans but that was already in use, so changed to Malvastrum niveus. Translate those and you get fragrant-snow bushmallow, which at least is better than San Luis Obispo County bushmallow as there are many taxa of Malacothamnus in San Luis Obispo County. The old common names are still on iNat and you can still use them but I've changed the default common name for both to be in sync with the new treatment.

See more details in my new treatment of Malacothamnus, which you can download for free here.

I've made a few changes to Malacothamnus fasciculatus on iNat.

Malacothamnus fasciculatus var. laxiflorus was lumped into var. fasciculatus for many years. My research shows that it is distinct, maybe distinct enough to be recognized as a species. It needs more research though, so I'm splitting it back out as just a variety of M. fasciculatus. Vars. laxiflorus and fasciculatus are mostly distinct geographically but intergrade near the border or Orange and San Diego Counties. So that will be the problem area for identification. Var. laxiflorus may also be planted in parts of San Diego County, so that is something to watch for.

My research showed Malacothamnus fasciculatus var. nuttallii to be morphologically, phylogenetically, and geographically distinct from the rest of M. fasciculatus. It also blooms roughly one month later than the other M. fasciculatus varieties growing at similar elevations. So, the new treatment returns M. fasciculatus var. nuttallii back to the species rank as M. nuttallii.

I've added the suggested common name "southern coastal bushmallow" as a common name for both M. fasciculatus and M. fasciculatus var. fasciculatus. Ideally, this will become the default common name but as there are so many observations of M. fasciculatus on iNat, it might be good to hold off on that to see what other websites end up doing.

See more details in my new treatment of Malacothamnus, which you can download for free here.

I've added two varieties of Malacothamnus densiflorus to iNat from my new treatment of Malacothamnus, which you can download for free here.

Malacothamnus densiflorus var. viscidus is a rare taxon from the Otay Mountain region of San Diego County, CA and Baja California (range map on taxon page). It is distinguished from the rest of M. densiflorus by relatively long glandular hairs throughout the plant and well as denser stellate hairs on the calyx tube. It also generally has a greasy feel to the leaves and a rancid odor. The glandular trichomes often dry emerald green in color and somewhat resemble unicorn horns, so I've given this one the common name emerald unicorn bushmallow.

The rest of Malacothamnus densiflorus is now assigned to the variety Malacothamnus densiflorus var. densiflorus, which has shorter glandular hairs throughout and sparser stellate hairs on the calyx tube. One thing that really makes M. densiflorus stand out from other Malacothamnus is that stellate hairs on the calyx generally have much fewer rays (branches) than other species. My suggested common name for the species is few-rayed bushmallow, which refers to this. As this common name is actually useful in identification, I've made it the default common name on iNat for this species. The other common names like many-flowered bushmallow are still on iNat and will come up if you type them in but are best avoided as they describe many different species of Malacothamnus and cause misidentifications as a result.

I've updated my IDs for observations of M. densiflorus var. viscidus and, when identifiable to variety, M. densiflorus var. densiflorus in and near the range of var. viscidus. I'm not sure when/if I'll get to identifying the rest of the range of M. densiflorus var. densiflorus. If someone else wants to work on that, go for it. Outside of the range of M. densiflorus var. viscidus, all M. densiflorus should be var. densiflorus with the exception of a couple plantings of var. viscidus outside of its range. See range maps both on iNat and the new treatment. Feel free to ask if you have any questions.

I've added three new species to iNat from my new monograph of Malacothamnus, which you can download for free here. Each new species is described in Volume 2 of the monograph, which has more details, and also included in the treatment in Volume 3, which has more photos.

Malacothamnus astrotentaculatus - Starry-tentacled Bushmallow.
This is the northernmost species in the genus, the range of which was expanded by an iNaturalist observation. It is endemic to Shasta and Tehama counties. This one needs more people looking for it in recently burned areas to help figure out the extent of its range.

Malacothamnus discombobulatus - Discombobulating Bushmallow.
This is what used to be the disjunct northern populations of Malacothamnus davidsonii. It is endemic to Monterey and San Luis Obispo counties. Malacothamnus davidsonii is now restricted to the Tujunga region of Los Angeles County and I suggest using the common name Tujunga bushmallow for M. davidsonii now to reduce confusion between these two species and to raise awareness that it is a narrow endemic to that region. Davidson's bushmallow is still set as the default common name on iNat for M. davidsonii as that will connect to most other websites. This may change in the future if other websites start adopting my suggested common name.

Malacothamnus eastwoodiae - Alice's Lovely Bushmallow.
This one has the smallest range of all Malacothamnus species and is currently only known from Vandenberg Space Force Base in Santa Barbara County.

I've published my PhD research, which you can download for free here. This is a three-volume open-access monograph on the genus Malacothamnus. Most people will only be interested in the third volume, which is a new treatment of the genus with a geographically focused identification key, lots of photographs, preliminary conservation assessments, and general information on the genus. For those who want to dig deeper, the first two volumes go into the details of the evidence used in making the taxonomic decisions for the treatment.

I'll be working on updating the Malacothamnus taxonomy on iNaturalist but it may take some time to complete everything, especially as I want to make it as smooth of a transition as possible. I hope to have all changes done by the time the Jepson eFlora version of the treatment comes out in winter 2023/24.

As well as changing some scientific names, I will also be adding some new common names, which might take some getting used to but will likely ultimately be to everyone's benefit. Some of the common names that have been used on iNaturalist in the past have led to a lot of misidentifications, have been attributed to many different taxa, or honor people who led massacres. I'll be adding some common names that might not all be helpful in themselves but will hopefully eventually be used more than those that cause problems. When possible, I tried to think of a common name that will help reduce misidentifications. See Volume 3 of the monograph for explanations of these.

Perhaps I'll give updates in the journal as I make changes so you can see what I'm doing and give you a little more detail on each change.

Thanks to everyone who has contributed to this project! I couldn't have done it without you!

I've updated two of the draft keys to Malacothamnus available on my website if you'd like to try them out. One is for San Diego, Orange, and Riverside counties plus Baja California. The other is for Kern, Los Angeles, San Bernardino, and Ventura counties. Each of these keys expands the previous region covered, includes more taxa, and has hopefully improved couplets. Feedback is appreciated if you use these as that could improve the final key for the new Jepson treatment. Some other regional keys are also available and I plan to update them soon. Regions not yet covered will eventually make it there too.
Keys available here: http://keiriosity.com/malacothamnus/

This project is getting close to being done. The new treatment should be out sometime in 2023.

I recently did my dissertation defense and created a video version of the presentation if anyone wants to see some of what the data from this project helped with. You can watch here:
https://www.youtube.com/watch?v=k29aOdSsomM

While it can be tricky to identify some Malacothamnus due to lots of overlapping morphological characters in the keys, most don't overlap geographically. If you are in an area where only one taxon is known, you can usually be pretty sure of the ID based on that, assuming that it is a wild plant and wasn't introduced in a restoration project. If only two or three taxa grow in that area, that also helps narrow down the possibilities. To address this, I've uploaded rough ranges of Malacothamnus taxa to iNaturalist. These will be updated with improved maps as this project progresses.

The image above is the range map of M. fremontii, which you can view an interactive version of here. The pink is the range I have uploaded, the green are counties where there are iNaturalist observations, and the orange is where someone put it on a list for a county where it may or may not actually occur. Malacothamnus orbiculatus has often been confused with M. fremontii and sometimes lumped into it. Compare its range here or on the map below and you'll see there is only a small area where they overlap and likely intergrade/hybridize (near the "S" in "Sequoia National Forest").

iNaturalist observation maps can get pretty messy for rare plants as iNaturalist obscures the coordinates. This is a very good thing for some species that really need that protection but a one-size-fits-all approach to the 1000+ rare plant species in California is more of an impediment to conservation for most (see views on that debate here). A rough range map doesn't give exact locations but does give you a better idea of where something may occur. See the range map of M. palmeri here and below. Once again, the two larger pink polygons is the known range. All the smaller circles of a similar color are obscured iNaturalist observations. Not a single one is in the known range of the species and most would have you believe this shrub is an ocean dwelling organism.

Many people have shared their coordinates with this project, which has been useful in making these rough range maps. This data will be used in creating better maps for the new treatment of the full genus I'm working on as well as for conservation assessments. There are many people out there that have observations with obscured coordinates that have not shared them with this project. I will tag all these people below. If you are one of them and would like to contribute plant locations to this project, see the instructions here to share your coordinates with the project. Thanks to all who have and will contribute!

Update Feb. 2023 - I have removed tags to people that had obscured coordinates as I'm mostly done with this research and many of the Malacothamnus taxa that were originally obscured on iNaturalist are no longer. Thanks to all who have helped with this project!