Two Varieties of Malacothamnus densiflorus added to iNat

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.

Posted on August 27, 2023 03:50 PM by keirmorse