Xanthoparmelia
Xanthoparmelia (Vain.) Hale, 1974
| Common name | Rockfrogs |
|---|---|
| Field Characters | Medium-sized to large, leafy chlorolichens to 10 cm across. Thalli vary from unattached (vagrant) to tightly attached throughout. Lobes may be narrow and angular to wide and rounded. Upper surface pale yellow, typically shiny, sometimes with immersed pycnidia. Vegetative propagules present in some species as lobules or isidia, never soredia. Lower cortex typically brown to black, with relatively abundant, simple to sparsely branching rhizines concolorous with the lower cortex. Apothecia common in some species, laminal, concentrated centrally, on short stipes, with brown discs and yellow thalline rims. |
| Similar species & genera |
Arctoparmelia: saxicolous, never terricolous, upper cortex dull, lower surface whitish to grey to purplish black. Never lobulate or isidiate, some species sorediate. Medulla UV+ blue-white. |
| Ecology | Terricolous or saxicolous. Most common in the grasslands, occasional in the shield and mountain regions. |
| Chemistry | Upper cortex PD+ pale yellow or PD-, K-, C-, KC+ yellow, UV- (usnic acid). Medullary chemistry complex, variable and apparently not a good taxonomic trait, always UV-, may be PD- or PD+ yellow to red, K- or K+ yellow to red. |
| Molecular support |
Poor at the species level. Multiple studies have found that historical morphological and chemical traits do not correspond well to molecular clades (Leavitt et al. 2011a, b). Until more extensive molecular work is done, we continue to follow historical morphological species delimitation. |
| Links |
Species recorded in Alberta: 10 estimated, but molecular work needed.
- X. angustophylla (Gyelnik) Hale
- X. camtschadalis (Ach.) Hale Syn.: Parmelia camtschadalis (ABMI)
- X. chlorochroa (Tuck.) Hale Syn.: Parmelia chlorochroa (ACIMS, ABMI)
- X. coloradoensis (Gyelnik) Hale (ACIMS, ABMI)
- X. conspersa (Ehrh. ex Ach.) Hale Syns.: Parmelia conspersa, P. isidiata (ACIMS, ABMI)
- X. lineola (E. C. Berry) Hale Syn.: Parmelia lineola (ACIMS, ABMI)
- X. mexicana (Gyelnik) Hale Syn.: Parmelia mexicana (ACIMS, ABMI)
- X. subdecipiens (Vainio) Hale Syn.: Parmelia subdecipiens (ACIMS)
- X. stenophylla (Ach.) Ahti & D. Hawksw. Syn.: Parmelia stenophylla, Xanthoparmelia somloënsis
- X. wyomingica (Gyelnik) Hale Syn.: Parmelia wyomingica (ACIMS, ABMI)
Click for pdf key to the Xanthoparmelia in Alberta v2025
RENR Students: Know Xanthoparmelia camtschadalis & X. wyomingica – be able to key these species out or recognize them (also covered in Brodo et al. 2001 and Goward et al. 1994).
Resources
Ahti, T. & D. L. Hawksworth. 2005. Xanthoparmelia stenophylla, the correct name for X. somloënsis, one of the most widespread usnic acid containing species of the genus. The Lichenologist 37: 363-366.
Brodo, I. M. 2016. Keys to the lichens of North America. Revised and Expanded. Yale University Press, in collaboration with the Canadian Museum of Nature.
Brodo, I. M., S. D. Sharnoff, and S. Sharnoff. 2001. Lichens of North America. Yale University Press, New Haven and London.
Goward, T., B. McCune, and D. Meidinger. 1994. The Lichens of British Columbia Illustrated Keys. Part 1 – Foliose and Squamulose Species. Ministry of Forests Research Program, Province of British Columbia.
Hale, M. E. 1990. A synopsis of the lichen genus Xanthoparmelia (Vainio) Hale (Ascomycotina, Parmeliaceae). Smithsonian Contributions to Botany 74: 1-250.
Leavitt, S. D., L. A. Johnson & L. L. St. Clair. 2011a. Species delimitation and evolution in morphologically and chemically diverse communities of the lichen-forming genus Xanthoparmelia (Parmeliaceae, Ascomycota) in western North America. American Journal of Botany 98: 175-88. doi: 10.3732/ajb.1000230. Epub 2011 Jan 25. PMID: 21613107.
Leavitt, S. D., L. A. Johnson, T. Goward & L. L. St. Clair. 2011b. Species delimitation in taxonomically difficult lichen-forming fungi: an example from morphologically and chemically diverse Xanthoparmelia (Parmeliaceae) in North America. Molecular Phylogenetics & Evolution 60: 317-32. doi: 10.1016/j.ympev.2011.05.012. Epub 2011 May 25. PMID: 21627994.
