Taxon Report

Malacothamnus mendocinensis (Eastw.) Kearn.

Mendocino bushmallow

Print Report


© 2021 Keir Morse

Taxon Summary

Malacothamnus mendocinensis, commonly known as Mendocino bushmallow, is a perennial deciduous shrub in the Malvaceae that is found only in California. It occurs within Chaparral, and Cismontane woodland, growing at elevations from 215 to 230 meters. Malacothamnus mendocinensis is ranked 1B.1, Plants Rare, Threatened or Endangered in California and Elsewhere; Seriously threatened in California.


  Classification

Scientific Name:
Malacothamnus mendocinensis (Eastw.) Kearn.
Common Name:
Mendocino bushmallow
Family: Malvaceae
Element Code: PDMAL0Q0D0
USDA Plants Symbol:
Synonyms/Other Names:

Ecology and Life History

Lifeform: perennial deciduous shrub
Blooming Period: Jun-Aug Jun-Aug
Elevation: 215-230 (705-755)
General Habitats: Chaparral, Cismontane woodland
Microhabitat: Roadsides, Rocky
Microhabitat Details:

Occurrence Data from the CNDDB

Total Occurrences: 2
Element Occurrence Ranks:
   Excellent (A) 0
   Good (B) 0
   Fair (C) 0
   Poor (D) 1
   None (X) 1
   Unknown (U) 0
California Endemic:  True
California Counties and Islands: Name (Code)
Mendocino (MEN)*
Quads: Name (Quad Code)
Elledge Peak (3912312)*, Ukiah (3912322)

Threat List Data from the CNDDB

Threat List Total: 5
EOs with Threat Listed: Total EOs % of EOs
2 100 %
Dam/Inundation 1 50%
Improper burning regime 1 50%
Non-native plant impacts 1 50%
Other 1 50%
Road/trail construction/maint. 1 50%

Notes

Rediscovered at Lake Mendocino in 2016 by J. Xerogeanes. Originally known from only two historical collections near Ukiah (last in 1939). Reason for disappearance likely due to lack of wildfire.
Threats:
Highly threatened by inundation, fire suppression, and recreational activities. Possibly threatened by road maintenance, herbivory, and competition with weeds.
Taxonomy:
A synonym of M. fasciculatus in TJM (1993). Not recognized in TJM 2 2012 but recognized in Jepson eFlora 2023 treatment. Current research indicates M. mendocinensis is separated morphologically and phylogenetically from other species in the genus.

Selected References

Proposed Change from CRPR 1A, GXQ / SX to 1B.1, G1 / S1 (2023)
Leaflets of Western Botany 2:188 (1939)
Leaflets of Western Botany 6:113-140 (1951)
Citation California Native Plant Society, Rare Plant Program. 2025. Rare Plant Inventory (online edition, v9.5.1). Website https://www.rareplants.cnps.org [accessed 27 January 2025].