Download Thelenella muscorum var. octospora

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 nonstaining 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
1
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 FremontWinema NF.
Widespread globally but rare in the Pacific Northwest, where probably
undercollected. Ranked S4S5 in Saskatchewan, where presumably wellcollected.
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
2
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: 294304.
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.
3
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.
4