Cystotheca lanestris

Cystotheca lanestris
Cystotheca lanestris witch's broom symptom on Quercus agrifolia in California.
Scientific classification
Kingdom:	Fungi
Division:	Ascomycota
Class:	Leotiomycetes
Order:	Erysiphales
Family:	Erysiphaceae
Genus:	Cystotheca
Species:	C. lanestris
Binomial name
Cystotheca lanestris (Harkn.) Miyabe, 1909
Synonyms
Sphaerotheca lanestrisHarkn., 1884 Albigo lanestris(Harkn.) Kuntze, 1898 Cystotheca lanestris(Harkn.) Sacc., 1911 Oidium ventricosumHarkn., 1884

Cystothecalanestris (commonly known as the live oak witch's broom fungus) is a species of powdery mildew in the family Erysiphaceae. It is found in North America on plants in the genus Quercus . Its primary range is south-western United States and north-western Mexico, mostly along the coast where its preferred host plants are found. ^[1]

Cystotheca lanestris mycelium on the underside of a Quercus leaf in California.

Description

Cystotheca lanestris forms white mycelium turning grey to tan brown with age. ^[2] It induces witch's-broom galls – abnormal clusters of shoots that are thickened, elongated and highly branched with very small leaves. ^[3] Cystothecalanestris, like most Erysiphaceae, is fairly host-specific and only infects species in the genus Quercus . Within this genus however, it is found on a rather large selection of oak species, including Quercus agrifolia , alba, bicolor, canbyi , cerris , chrysolepis , coccinea , crassipes , douglasii , engelmannii , garryana , ilex , kelloggii , laceyi , laeta, laurifolia , lobata , macrocarpa , michauxii , nigra , obtusata , palmeri , palustris , phellos , polymorpha , potosina , robur , rubra , stellata , suber , toumeyi , velutina , virginiana , and wislizeni . ^[4] Asian collections previously assigned to this species belong to a phylogenetically different species, C. kusanoi . Another species infecting Quercus in North America, Cystotheca mexicana , is endemic to Mexico and is found on similarly endemic oaks. ^[4]

Taxonomy

The fungus was formally described in 1884 by Harkness with the basionym Sphaerotheca lanestris. The species was transferred to the genus Cystotheca in 1909 by Miyabe.

References

1. Russo, Ronald A. (2021). Plant Galls of the Western United States. Princeton University Press. pp. 91–92. doi:10.1515/9780691213408. ISBN   978-0-691-21340-8. LCCN   2020949502.
2. Braun, Uwe; Cook, Roger T. A. (2012). Taxonomic manual of the Erysiphales (powdery mildews). CBS biodiversity series. Utrecht: CBS-KNAW fungal biodiversity centre. ISBN   978-90-70351-89-2.
3. Swiecki, Tedmund J.; Bernhardt, Elizabeth A. (2006). A field guide to insects and diseases of California oaks (Report). Albany, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station. doi:10.2737/psw-gtr-197.
4. Bradshaw, Michael; Braun, Uwe; Quijada, Luis; Coombes, Allen J.; Contreras-Paredes, Carlos; Pfister, Donald H. (2023-05-04). "Phylogeny and taxonomy of the genera of Erysiphaceae, part 3: Cystotheca" . Mycologia. 115 (3): 427–436. doi:10.1080/00275514.2023.2194172. ISSN   0027-5514. PMID   37159342.

External links

• gallformers.org - Cystotheca lanestris