Cliostomum griffithii (Sm.) Coppins

Thallus areolate, cracked, granular or smooth, pale grey, greenish, or creamy white, usually with conspicuous, concave, black pycnidia bearing bacilliform or narrowly tear-drop shaped conidia 3-5 × 1.3-2  µ; apothecia matte, 0.2-0.8 (‑1.5) mm wide, pink, grey or blackish, generally pale-grayish pruinose, the rim usually distinctly paler than the disc; hymenium 45-60  µ high, topped with abundant crystals, and also often with a brownish, K+ purplish pigment; spores 1-septate, oblong or narrowly elliptical, 8-16 × 3-5  µ.

Reactions: Thallus K+ yellow, PD+ yellow.

Contents: Atranorin, chloroatranorin, roccellic acid, fatty acids, sometimes also with caperatic acid or a trace amount of usnic acid.

Habitat: Common on branches of conifers and shrubs in rain-sheltered sites, often also on the underside of leaning snags, lower to middle elevations.

Similar Species: The conspicuous black pycnidia on a pale crust are diagnostic, and the often mottled pink and grey apothecia are unmistakable.

Specimens: Björk 10842, 12404; Goward 96-1114.

Local Status: Very common.

Cliostomum cf. leprosum (Räsänen) Holien & Tønsberg

Thallus white or creamy white, smooth but quickly developing soredia diffusely over its surface, the soredia 200-100  µ wide; apothecia usually present, 0.25-0.6 mm wide, deep yellow-orange with tan tones, the rim thin but persistent, paler than the disc, and often becoming undulate in outline, the disc flat or low-convex; hymenium topped in abundant pale crystals; spores 9-13 × 2-3.5  µ; pycnidia few in number, black, concave, formed on the thallus surface, 0.2-0.6 mm wide; conidiospores 2-3 × 1.5-2  µ.

Reactions: K+ yellow, PD-.

Contents: Atranorin and caperatic acid, the apothecia also with usnic acid.

Habitat: On bark of Thuja and Tsuga in humid forests. Lower to middle elevations.

Similar Species: the combination of whitish thallus, black pycnidia, and typical Cliostomum apothecia set this species apart easily.

Specimens: Goward 96-924, 96-1197.

Local Status: Uncommon.

Notes: Some or all inland BC material may contain xanthones, producing a UV+ yellow-orange reaction (Cliostomum sp. nov. sensu T. Spribille, unpublished), but the few study area collections are UV+ blue-white or purplish white. More work is needed to determine whether more than one species is involved in our range.

Cliostomum pseudovitellinum Spribille ined. form 1

Thallus white or creamy whitish, areolate or granular, or in part smooth, rarely immersed; apothecia matte, usually becoming clustered or crowded together, deep yellow-orange with tan tones, with a thin and receding rim, the disc becoming convex and often botryoid; hymenium 45-65  µ high, topped with dense yellowish crystals; spores 1-septate, oblong or narrowly elliptical, 10-14 × 2.5-3.5  µ; conidiospores 3.5-5 × 1.2-1.7  µ, produced black, concave pycnidia produced on the thallus surface, these fewer and less conspicuous than those of C. griffithii.

Reactions: Apothecia KC+ deeper orange.

Contents: No known lichen substances in the thallus, but the apothecia containing usnic acid.

Habitat: On conifer bark and wood, usually at higher elevations or otherwise in cool, well lit, well-ventilated places, lower to middle elevations.

Similar Species: Lecanora symmicta may have a similar colouration of the thallus and apothecia, but the thallus almost always is either pale blue-green or with a stronger yellow tone (usnic acid). Cliostomum pseudovitellinum lacks usnic acid in the thallus, or nearly so, and its apothecia become crowded or clustered with maturity, while those of L. symmicta are usually evenly dispersed. The spores of L. symmicta are broader in outline.

Specimens: Björk 9831.

Local Status: Rare.

Cliostomum pulchellum Björk ined.

Thallus matte or somewhat glossy greenish grey, areolate, large-granular or squamulose (mostly subsquamulose-areolate), the thallus segements 0.15-0.5 mm wide, lacking a prothallus; apothecia matte, pale peach-tan, a very few discoloring with grey mottles, often with a light dusting of white pruina, 0.3-1 mm wide, with a waxy but matte appearance, the rim non-algal, a bit paler than the disc, prominent and persistent, usually at least slightly undulating, but receding on overmature apothecia, the disc flat to low-convex, sometimes constricting at the base at overmaturity; exciple with streaks of tiny pale gold crystals in outer portions; hymenium 30-35  µ high, upper portions densely inspersed with tiny, pale gold granules; hypothecium colourless and lacking granules, the hyphae tending to be vertically oriented, especially where approacing the asci; spores narrowly oblong-elliptic, with 1 crosswall, each cell usually with two oil droplets the boundary between which may appear like two additional septae, 7-11 × 2-2.5  µ; pycnidia usually inconspicuous, flat jet-black smudges tucked between the areoles, most 0.1-0.2 mm wide, a few to 0.5 mm, the dark brown hyphae that produce the blackish colour of the pycnidia are K+ purple; conidiospores oblong to elliptical, 3-4 × 0.7-1.2  µ.

Reactions: Thallus K+ yellow, C-, KC-, PD+ yellow; apothecia K+ yellow, KC+ deep yellow-orange.

Contents: Unknown, but the KC+ reaction of the apothecia suggests usnic acid, which is found in apothecia of some other species in the genus.

Habitat: Twigs of Picea under rain-shedding foliar cones, rare on Acer bark in Picea rain-shelter. Lower elevations.

Similar Species: Cliostomum griffithii grows in similar habitats, but in wetter, cooler forest habitats and has wider conidia and pink-gray apothecia that are mostly grey-mottled. Some forms of Lecanora symmicta appear similar, but have simple spores and very long conidia.

Specimens: Björk 14383.

Local Status: Rare.

Notes: Differs from other species in the genus in its narrower conidiospores, peachy-tan apothecia and the strongly areolate to squamulose thallus. Approaches Cliostomum corrugatum, but differs in the less yellowish apothecia, longer conidia and narrower spores. Known only from inland BC.

Cliostomum viride Björk & Spribille ined.

Thallus yellowish green, olive-green or creamy yellow, smooth, verruculose, areolate or granular, waxy; apothecia deep orangish yellow or yellow-orange, the rim thin and inconspicuous but persistent, the disc becoming low-convex, often undulating; hymenium 45-60  µ high, topped in dense yellowish crystals; spores 1-septate, rarely 3-septate, narrowly elliptical or fusiform, 11-17 × 3-4.5  µ; pycnidia usually conspicuous, produced on the tops of areoles, 0.15-0.25 mm wide; conidiospores 1.5-2.2 × 0.8  µ, bacilliform or with one end swollen.

Reactions: K+ yellow, KC+ deep yellow-orange, PD-.

Contents: Unknown, but the thallus certainly with usnic acid.

Habitat: On bark of conifer trunks and branches, mostly at upper forested elevations.

Similar Species: Cliostomum flavidulum also produces abundant usnic acid in the thallus, but never produces the green tones of C. viride and its thallus is usually sorediate or scurfy.

Specimens: Björk s.n. (2 April, 2004), hb. Björk.

Local Status: Common.

Notes: This species is distributed commonly in subalpine forest from central inland BC south to Idaho.