Trapeliopsis
Crustose or squamulose lichens containing a trebouxioid alga; thallus smooth, areolate, granular, verrucose, sorediate, squamulose or somewhat foliose; apothecia usually with a thick, prominent and persistent non-algal rim, sometimes the rim receding and the disc becoming convex or divided into multiple rounded segments; hymenium colourless or with faint greyish pigment, also with minute crystals dispersed throughout, formed of densely branching and anastomosing paraphyses embedded in gel; hypothecium colourless; asci narrowly clavate, thin-walled or with a shallow tholus, IKI- or + pale blue; spores 8 per ascus, colourless, simple, elliptical to ovate, often with a single large oil droplet within.
References: Tønsberg 1992; Printzen & McCune 2004; Spribille 2006.
| 1a. | Apothecia consistently black whether young or old; rim quickly receding; thallus of masses of coarse granules and soredia, or with a few areoles, creamy off-white; to be sought …[Trapeliopsis viridescens (Schrader) Coppins & P. James] |
| 1b. | Apothecia charcoal grey, usually with creamy or pinkish tones, sometimes blackening with age; rim usually persistent; thallus almost always with abundant areoles, creamy grey, creamy green, greyish green, or blue-green …2 |
| 2a. | Thallus creamy grey, creamy green or less often greyish green or blue-green; areoles tightly packed or loose and haphazardly arrayed; soralia usually spreading or becoming confluent …Trapeliopsis granulosa |
| 2b. | Thallus greyish green or blue-green; areoles always tightly packed; soralia usually remaining discrete …Trapeliopsis flexuosa |
Trapeliopsis flexuosa (Fr.) Coppins & P. James
Thallus greyish blue or olive grey, of scattered to more often crowded areoles 0.1-0.6 mm wide, many producing 0.2-0.4 mm wide soralia on the top, or seldom from the side; soredia 15-30 µ wide, most not aggregated into consoredia, coloured like the thallus or sometimes bluish; apothecia uncommon, scattered or a few clustered, not crowded, 0.2-0.7 mm wide, the rim coloured like the disc or paler, the disc flat or low-convex, dark greenish grey or blackish, rarely pinkish-gray; rim non-algal; hymenium 40-50 µ high, containing abundant granules; upper hymenium medium to dark greenish grey, granular; hypothecium colourless; paraphyses thin and gnarled, richly branched and anastomosed; asci thin-walled except for the shallow tholus at the tip, IKI- or IKI+ pale blue; spores ovate, 6-9.5 × 2.5-4 µ.
Reactions: Thallus C+ red, KC+ red.
Contents: Gyrophoric acid.
Habitat: Logs, snag, old (50 yr) stump, bases of large trunks of Pseudotsuga, and once on a decorticated Pseudotsuga branch, lower to middle elevations.
Similar Species: Among C+ red sorediate crusts in the study area, this one is marked by its dense, bluish to olive-gray areoles and more-or-less concolourous soredia. Trapeliopsis granulosa has creamy yellowish tones in the thallus and larger spores. Trapeliopsis viridescens has a creamy whitish or pale grey-green thallus of small granules.
Specimens: Goward 91-2197; G. Thor 8465.
Local Status: Occasional.
Trapeliopsis granulosa (Hoffm.) Lumbsch
Thallus thickly areolate and granular, creamy whitish, pinkish grey, greenish grey, or charcoal grey, matte, often forming large patches, usually with soredia in randomly placed heaps atop the areoles; apothecia common, pink, grey or pinkish brown, often aging to blackish, 0.3-1(‑1.5) mm wide, the rim persistent or receding, the disc often becoming lumpy; spores 8-15 × 4-6 (‑7) µ.
Reactions: All parts C+ red (flash).
Contents: Gyrophoric acid and minor amounts of lecanoric acid.
Habitat: On soil, detritus, bark or wood, always within the winter snowpack. All forested elevations.
Similar Species: Trapeliopsis pseudogranulosa has been reported from our area, and may be found in the ESSF. It has orange patches that react K+ purple.
Specimens: Goward 96-1086.
Local Status: Common.