SPECIES FACT SHEET

Common Name: Chromatochlamys lichen

Scientific Name: Thelenella muscorum var. octospora

Recent synonyms: Chromatochlamys muscorum var. octospora, Pyrenidium octosporum

Division: Ascomycota

Class: Ascomycetes

Order: Uncertain (incertae sedis)

Family: Thelenellaceae

Taxonomic Note: All North American records for Chromatochlamys muscorum var. octospora refer to Thelenella muscorum var. octospora (Fryday and Coppins 2004).

Technical Description: Thallus crustose, 0.1-0.3 mm thick, white to greenish or bluish gray, smooth to roughened, dividing into irregular plates (areoles), occurring over substrate in scattered, irregular lumps or grape-like clusters. Fertile areoles somewhat inflated. Perithecia few, black, partially exposed and protruding from thallus, 0.3-0.5 mm in diameter, opening by a small black pore (ostiole), spore-bearing layer (hymenium) lacking algae. Asci 65 x 28 μm, club-shaped (clavate), double-walled (bitunicate), staining I+ (amyloid) at the thickened apical dome (tholus) except where the inner wall (endoascus) forms a non-staining peg-like apical extension into the tholus. Spores 8 per ascus, elliptical to elongate-ovoid, tapered more on one end than the other, cross-walls more or less patterned like a brick wall (submuriform to muriform), (20) 40-60 x (7) 12-20 μm, hyaline to brownish, thin-walled. Paraphyses hyaline, loose, slender, unbranched or sparingly branched. Photosynthetic partner (photobiont, phycobiont) is a green alga in the Trebouxia group (trebouxioid). (Looman 1962; Mayrhofer 1987; Thomson 1997; McCune 2006).

Chemistry: ascus tholus I- (Mayrhofer 1987; Thomson 1997; McCune 2006).

Distinctive characters: White to bluish lumpy thallus on soil, rock, or decaying mosses and lichens, with partially exposed black perithecia; pruinose; with 8 more or less muriform spores per ascus, the tholus not staining with iodine. Similar species: Thelenella muscorum var. muscorum has spores 60-90 x 15-25 μm and only 2-4 spores per ascus. Pyrenidium actinellum has immersed perithecia and 4 spores per ascus. Species of Protothelenella have ascus tips I+ blue, the alga Elliptochloris, and occur in damp montane to arctic-alpine habitats. Other descriptions and illustrations: Looman (1962, as Pyrenidium octosporum): 296; Mayrhofer (1987, as Chromatochlamys muscorum var. octospora): 17, 19, 73, fig. 1B, figs. 52-54; McCune (2006, as Chromatochlamys muscorum var. octospora): 10.

Life History: Details for Thelenella muscorum var. octospora are not documented. Dispersal is presumably by spores and fragmentation of the thallus or poorly consolidated soil substrate.

Range, Distribution, and Abundance: Interruptedly circumboreal. Western United States (California, Colorado, Oregon, Wyoming), western Canada (Saskatchewan), UK, Ireland, Scandinavia, Europe, Russia.

National Forests: documented on the Ochoco NF (Crooked River National Grassland, The Island RNA), suspected at lower elevations on the Deschutes, Malheur, Umatilla, and Wallowa-Whitman forests. BLM Districts: documented from Prineville (The Island RNA) District, suspected on the Lakeview, Spokane, and Vale districts (McCune 2004). The Burns District also suspects the species, as does the Fremont-Winema NF.

Widespread globally but rare in the Pacific Northwest, where probably undercollected. Ranked S4S5 in Saskatchewan, where presumably well-collected.

Habitat Associations: On soil, rock, and dead or dying mosses and lichens in dry woodland, prairie, shrub-steppe, and subalpine forest, up to 11,000 feet elevation (Weber and Wittman 1992). In the Pacific Northwest, Thelenella muscorum var. octospora is a component of biological soil crusts (previously called "cryptogamic," cryptobiotic," or "microphytic" crusts) in semi-arid shrub-steppe and grassland below elevations of 4,000 feet. Vegetation types are Juniperus occidentalis, Artemisia rigida, and Artemisia tridentata ssp. wyomingensis associations with Festuca idahoensis, Poa secunda, and Pseudoroegneria spicata. In Saskachewan, reported from Leptogium lichennoides (Looman 1962).

Threats: Grazing, OHV traffic, and to a lesser degree fire are the primary threats to Thelenella muscorum var. octospora because these are the three main factors that negatively impact biological soil crusts. Soil crusts are fragile and extremely vulnerable to being pulverized by livestock and vehicle tires. Tire tracks may remain visible up to 20 years after damage has occurred. Well-preserved biological soil crusts are rare in the Pacific Northwest because grazing has been so pervasive and few areas have escaped impacts. A few known sites are inaccessible to livestock or vehicles, while others have been excluded from grazing for up to 65 years and are in various stages of recovery.

Conservation Considerations: Revisit all known localities and monitor the status of the populations. Search for new populations on federal and state lands with high-quality biological soil crusts, particularly those with protected status. Survey for intact biological soil crusts in suitable habitat and protect the best sites.

Conservation rankings: Global: G4G5T4T5; National: NNR. Oregon Natural Heritage Information Center: List 3 (S2).

Preparer: John A. Christy, with edits from Daphne Stone

Date Completed: April 2009

Final edits: Rob Huff, BLM/FS

May 2010

References

Fryday, A.M. & B.J. Coppins. 2004. A reassessment of the genera Chromatochlamys and Thelenella, and a new species of Strigula from the British Isles. Lichenologist 36: 89-95.

Looman, J. 1962. Some lichens of Saskatchewan. Bryologist 65: 294-304.

Mayrhofer, H. 1987. Monographie der Flechtengattung Thelenella. Bibliotheca Lichenologica 26: 1-106.

McCune, B. 2004. Lichen species groups in the Columbia Basin; ecosystem functions and indicator values. Report to Eastside Ecosystem Management Project. Oregon State University, Corvallis. 51 pp.

http://www.icbemp.gov/science/mccune.pdf

Accessed 20 March 2009.

McCune, B. 2006. Key to the lichen genera of the Pacific Northwest. Oregon State University, Corvallis. 82 pp.

http://oregonstate.edu/~mccuneb/pnw.PDF

Accessed 20 March 2009.

Oregon Natural Heritage Information Center. 2007. Rare, threatened and endangered species of Oregon. Oregon Natural Heritage Information Center, Oregon State University. Portland. 100 pp.

http://oregonstate.edu/ornhic/2007_t&e_book.pdf

Thomson, J.W. 1997. American Arctic Lichens. 2. The Microlichens. University of Wisconsin Press, Madison. 675 pp.

Weber, W.A. & R.C. Wittman. 1992. Catalog of the Colorado flora: a biodiversity baseline. University of Colorado Press, Boulder. 215 pp.

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