Pertusaria
Crustose lichens containing a trebouxioid alga; crust smooth, scurfy, areolate, cracked, verrucose, isidiate or sorediate; apothecia usually deeply embedded in thalline warts, opening by a small pore, or a gaping disc, a few species with a ring-like thalline rim constricted at the base, or with a poorly organized disc or cluster of discs surrounded by loose, thin thalline flaps; hymenium formed of thin, densely branched and anastomosing paraphyses loosely embedded in gel, often with a grey, K+ mauve pigment in upper portions; hypothecium colourless; asci thick-walled, oblong, IKI+ blue only in a haze around the exterior, the apex not much thickened, but with a distinct, broad ocular chamber; spores 1-8 per ascus, colourless, simple, usually thick-walled, often with multiple wall layers, the inner and/or outer surface often textures with ridges, papillae or pits.
References: Dibben 1980; Lumbsch & Nash 2002; Spribille 2006; Spribille et al. 2009.
| 1a. | Thallus with granular soredia; apothecia usually absent …2 |
| 2a. | Soralia KC+ deep purple, usually in regular concentric or radiating patterns; common and widespread …Pertusaria amara |
| 2b. | Soralia KC-, haphazardly arranged …3 |
| 3a. | Thallus mostly immersed; soralia mostly concave or flat, soredia not much heaped up; usually growing on wood, especially on logs, also on bark of trunks; common in our area …Pertusaria pupillaris |
| 3b. | Thallus surficial and well developed; soredia heaped up, soralia never concave; usually growing on bark, especially of branches and twigs, seldom on wood; occasional …Pertusaria borealis |
| 1b. | Thallus lacking soredia, or appearing sorediate due to tufts of medullary material on the surface of the fertile verrucae, these not granular; almost always fertile …4 |
| 4a. | Apothecial disc pruinose or so densely covered with medullary material as to appear like soralia …5 |
| 5a. | Apothecial rim formed of fissured, concentric bands of thalline tissue; spores 8 per ascus, 9-28 × 5-15 µ …Pertusaria subambigens |
| 5b. | Apothecia rarely with concentric rings of thalline tissue; spores 1 per ascus, 90-200 × 30-80 µ …6 |
| 6a. | Thallus cortex K+ yellow, PD+ orange-red; crust comparatively thin, at least in young thalli, glossy, smooth to verrucose; apothecia usually widely separated; to be sought …[Pertusaria multipuncta (Turner) Nyl.] |
| 6b. | Thallus cortex K-, PD-; thallus comparatively thick, verrucose and matte; apothecia usually densely crowded …7 |
| 7a. | Algal medulla K+ yellow, PD+ orange-red; thallus margin often zonate; verrucae often as high as wide …Pertusaria multipunctoides |
| 7b. | Thallus and apothecia K-, PD-; thallus margin not zonate; verrucae almost always shorter than wide …Pertusaria ophthalmiza |
| 4b. | Apothecia never pruinose, never soralia-like, with an exposed disc, or apothecia opening by radiating fissures, or perithecioid and opening by a tiny pore …8 |
| 8a. | Apothecial disc pink, salmon or orange, rarely with any grey or blackish hue; spores 8 per ascus …9 |
| 9a. | Apothecia lumpy, with multiple segments of hymenial tissue separated by thin strips of medullary or thalline tissue; rim obscure and poorly developed, either receded, or partly hidden by strips of thalline tissue …10 |
| 10a. | Apothecia erumpent, pushing up radial strips of thalline material, remaining flat or low-convex; thallus creamy green, often immersed …Pertusaria mccroryae ined. |
| 10b. | Apothecia sessile, sphaerical, constricted at the base, lacking strips of thalline material, but the disc often interrupted by medullary tissue; thallus grey-green, surficial, smooth to verruculose …[Pertusaria sphaerica Björk ined.] |
| 9b. | Apothecia never lumpy, clearly with a single, uninterrupted disc and a distinct rim (that may be partly covered by strips of thalline tissue, but obviously distinct and well developed) …11 |
| 11a. | Apothecia C+ pink, gyrophoric acid present, with a thin, papery, radially segmented rim, the disc flat; spores 16-42 × 10-16 µ; common and widespread …Pertusaria carneopallida |
| 11b. | Apothecia C-, gyrophoric acid lacking, with a prominent, unsegemented rim, the disc concave to flat; spores 28-55 × 13-25 µ; uncommon, coastal and inland …Pertusaria diluta |
| 8b. | Apothecial disc grey or blackish or disc hidden beneath a thick, smooth mound of corticate tissue that opens only by a tiny black pore; spores often less than 8 per ascus …12 |
| 12a. | Disc gaping, at least at maturity; spores 54-134 × 26-69 µ …Pertusaria stenhammari |
| 12b. | Disc set within a chamber lined with thalline tissue that opens by a tiny pore, or in overmature apothecia the pore may eventually gape widely; spores various …13 |
| 13a. | Verrucae lacking grey smudges, usually with 3 or more ostioles; outer walls of healthy spores at least 5 µ thick, mostly appearing gelatinous in spores outside the ascus, expanded to 40 µ thick; to be sought in humid sites …[Pertusaria gelatinosa Björk ined.] |
| 13b. | Apothecia with at least a slight grey smudge around the usually single ostiole; spores with walls up to 8 µ thick …14 |
| 14a. | Spores 4-8 per ascus, 40-110 × 20-60 µ …Pertusaria sp. 6 |
| 14b. | Spores 8 per ascus, 18-46 × 10-32 µ …Pertusaria sommerfeltii |
Pertusaria amara (Ach.) Nyl.
Thallus continuous, smooth, moderately thick, pale bluish grey or green, with evenly spaced, concave soralia 0.5-1.5 mm wide; soredia contrastively paler than the crust, coarsely granular, 60-100 µ wide; apothecia rare, not seen in any specimen from BC; spores 1 per ascus, 130-150 × 40-50 µ, with walls about 8 µ thick.
Reactions: Soredia KC+ purple.
Contents: Picrolichenic acid and minor amounts of protocetraric acid.
Habitat: On bark, less often wood, of trunks and branches, usually above the winter snowpack. Lower to middle elevations.
Similar Species: No other species in our study area has KC+ purple soredia, and also characteristic is the combination of large soredia in convex soralia that are contrastively paler than the thallus.
Specimens: Björk 12478; Goward 94-900, 96-1122.
Local Status: Occasional.
Pertusaria borealis Erichsen
Thallus smooth or with scattered areoles, greenish grey or bluish grey, waxy, usually inconspicuous, with rather evenly spaced, round, high-convex soralia of various sizes up to 1.5 (‑3) mm wide, the soredia pale greenish grey, creamy white or bluish white, 40-80 µ wide, some tightly clustered into consoredia up to 200 µ wide; apothecia rare, not seen in material from the study area, 0.3-0.7 mm wide, at first covered in fluffy pruina, soredia and calcium oxalate crystals, with a pinkish disc below; hymenium about 120 µ high; spores broadly elliptical, 18-20 × 10-14 µ, with a single wall about 1 µ thick.
Reactions: Medulla and soredia PD+ red.
Contents: Fumarprotocetraric acid, cph-2, succinprotocetraric acid, and ± protocetraric acid.
Habitat: On acidic bark or wood, most often seen on Betula bark or on conifer snags, lower to middle elevations.
Similar Species: Pertusaria pupillaris and Ramboldia cinnabarina are similar in appearance, but are more common and have flatter soralia.
Specimens: Björk 8999.
Local Status: Uncommon.
Pertusaria carneopallida (Nyl.) Anzi
Thallus continuous and smooth, thin and filmy, creamy whitish, somewhat translucent when wet, soredia lacking; apothecia common, flat, scarcely raised above the crust, with a thin rim formed of thalline flaps that peel back to expose the pale orange-pink disc, whole apothecia often becoming dislodged, leaving holes in the thallus; spores 8 per ascus, 16-42 × 10-18 µ, with walls about 3 µ thick.
Reactions: Apothecia and medulla usually C+ and KC+ reddish (rapidly fading).
Contents: Gyrophoric acid usually present.
Habitat: On smooth bark, especially of ericaceous shrubs or Alnus, within the winter snowpack. All forested elevations, but especially middle and upper elevations.
Similar Species: Anzina carneonivea is somewhat similar macroscopically, but has much smaller apothecia and septate spores.
Specimens: Björk 9043; Goward 01-213.
Local Status: Common.
Notes: No other species of upper elevation forests has apothecia that regularly dislodge, leaving round holes in the thallus.
Pertusaria diluta Björk, G. Thor & T. Wheeler
Thallus areolate or cracked, light green or whitish; apothecia produced in thin-walled warts formed of thalline material, an inner rim quickly forming and becoming the dominant rim, this thick and persistent, curling slightly inward over the disc, algae sometimes present in the lower part of the exterior, but absent below the hypothecium; hymenium 85-195 µ high, colourless; spores 8 per ascus, 30-40 × 17-21 µ, with a single wall layer 1-2 µ thick.
Reactions: UV+ orange.
Contents: A single unknown substance.
Habitat: On conifer wood and bark of logs and trunks in humid forest, sometimes on twigs in the wettest forest, lower to middle elevations.
Similar Species: Pertusaria carneopallida and P. mccroryae are similar and may be related. The former has a very thin, papery apothecial rim and grows on smooth bark of broad-leaf shrubs. The latter has amorphous, rimless apothecia with a compound disc.
Specimens: Goward 96-1190; Goffinet 3717.
Local Status: Rare.
Notes: Known only from BC, northern Idaho and northwestern Montana.
Pertusaria mccroryae Björk, Spribille & Goward ined.
Thallus thin, continuous and smooth, or with a few scattered, flat areoles, creamy whitish, or immersed, soredia lacking; apothecia common, sparse or dense but almost always solitary, convex, not constricted at the base, with an indistinct rim formed of flaps of thallus tissue, often with multiple discs crowded together, the discs and thalline flaps pale orange-tan or pinkish; hymenium K+ yellow; spores 8 per ascus, 34-59 × 16-25 µ, with walls about 1 µ thick.
Reactions: Apothecial disc K+ yellow-orange.
Contents: Unknown.
Habitat: On bark and wood within the snowpack, especially on conifer logs and ericaceous shrubs. Lower to (especially) upper forested elevations.
Similar Species: Fertile specimens of Xylographa vitiligo may have similarly amorphous apothecia with multiple discs, but each disc is distinctly rimmed, and the thallus is sorediate.
Specimens: Björk 12876.
Local Status: Occasional.
Notes: This undescribed species is probably related to Pertusaria carneopallida and P. diluta, from which it sharply differs in having amorphously formed, convex apothecia. Known only from inland BC, northern Idaho and northwestern Montana.
Pertusaria multipunctoides Dibben
Thallus grey, greenish grey or yellowish grey, continuous and smooth or moderately lumpy, rarely areolate, often zonate (with alternating bands of dark and light colours lining the margins); apothecia contrastively paler than the crust, with a weakly corticate rim, usually producing loose, soredia-like masses of medullary material on the surface; spores 1 per ascus, 65-195 × 20-70 µ, with walls about 5 µ thick.
Reactions: Medulla K+ yellow turning brown, PD+ orange-red.
Contents: Fumarprotocetraric and succinprotocetraric acids, and minor amounts of protocetraric acid.
Habitat: On bark of conifer trunks, usually above the winter snowpack. Lower elevations.
Similar Species: Pertusaria multipuncta is very similar and is best distinguished by the chemistry, but it tends to have a thinner thallus and more solitary, widely separated apothecia. Pertusaria ophthalmiza has apothecia that are usually much shorter than wide, and is not zonate.
Specimens: Björk 10761; Goward 96-710.
Local Status: Occasional.
References: Dibben (1980).
Notes: This is a highly variable species not always easy to distinguish from similar species.
Pertusaria ophthalmiza (Nyl.) Nyl.
Thallus grey, greenish grey or yellowish grey, continuous or moderately lumpy, rarely areolate, not zonate around the margins (lacking alternating bands of dark and light colours lining the margins), but sometimes with a slightly differently coloured outline where the thallus abuts adjacent crust lichens; apothecia contrastively paler than the crust, with a weakly corticate rim, usually producing loose, soredia-like masses of medullary material on the surface; spores 1 per ascus, 70-200 × 25-75 µ, with walls about 5 µ thick.
Reactions: Spot tests all negative.
Contents: No known lichen substances.
Habitat: On bark of conifer trunks and branches, usually above the winter snowpack. Lower to middle elevations.
Similar Species: See notes under Pertusaria multipunctoides. May appear similar to some forms of P. subambigens, which differs most distinctly in having 8 spores per ascus.
Specimens: Björk 9846, 12289.
Local Status: Occasional.
Notes: Two or three undescribed species are currently lumped under this species, but these forms are most likely to be limited to lower elevations.
Pertusaria pupillaris (Nyl.) Th. Fr.
Thallus thin, smooth and continuous, pale grey, greenish grey or bluish grey, or (more often) immersed, producing round or unevenly shaped, flat or low-convex soralia 1-1.5 mm wide; soredia white or creamy white, 25-40 µ wide, often grouped into clusters 80 µ wide; apothecia rare, not yet seen in our study area, Lecanora-like, with a thick but receding thalline rim and a dark brownish grey disc; spores 8 per ascus, 10-14 × 7-11 µ, with walls about 1 µ thick.
Reactions: K+ dingy yellow, PD+ orange-red.
Contents: Fumarprotocetraric acid, and minor amounts of protocetraric acid.
Habitat: On wood and bark, usually within the winter snowpack.All forested elevations.
Similar Species: Pyrrhospora cinnabarina appears very similar, but has soralia that react bright yellow in K. Pertusaria borealis has rounder, distinctly convex soralia and a more often surficial thallus.
Specimens: Björk 12402.
Local Status: Occasional.
References: Purvis et al. (1992); Tønsberg (1992).
Pertusaria sommerfeltii (Flörke) Fr.
Thallus smooth, cracked or verruculose, pale grey, pale green-gray or yellowish grey, waxy; apothecia produced within warts coloured like the thallus, these 0.2-1.2 mm wide, opening by 1-5 small pores with a dark greyish halo around each pore; hymenium 150-250 µ high, greyish brown in upper portions, the pigment K+ mauve; spores18-46 × 10-32 µ, with a 2-layered wall, both layers smooth, the ends of the inner layer bulging into the lumen, at least at some stages of development.
Reactions: K- or + yellow, KC+ yellow, UV- or + yellowish.
Contents: 4,5-dichloronorlichexanthone and stictic acid, and ± constictic acid and unknown substances.
Habitat: On conifer bark, mostly on branches, in humid, well-lit forest habitats. Lower to (rarely) upper forested elevations.
Similar Species: Pertusaria gelatinosa and P. sp. 6 may appear very similar, but both have a much larger spores.
Specimens: Björk 12239, 14410.
Local Status: Uncommon.
Pertusaria stenhammari Hellb.
Thallus smooth, verruculose or cracked, matte or waxy, pale grey or greenish grey; apothecia produced within scattered or loosely clustered warts coloured like the thallus, these 0.2-1.2 mm wide, at first opening by a small pore, but the pore gaping with maturity, the disc dark grey and with a grey halo around it on the thalline tissue of the wart; hymenium 130-260 µ high, greyish brown in upper portions, the pigment K+ mauve; spores mostly 2 per ascus, 60-120 × 30-65 µ, with a single wall layer 2-16 µ thick, the inner surface bulging into the lumen, at least in some stages of development.
Reactions: All spot tests negative.
Contents: No known lichen substances.
Habitat: On conifer bark in humid, well-lit forests, especially on conifer branches in the dripzones of aspen and cottonwood (Populus). All forested elevations.
Similar Species: Megaspora verrucosa has a similar appearance, but has crowded apothecia and much smaller spores with thinner walls.
Specimens: Björk 13168, 14283; Goward 02-2133.
Local Status: Uncommon.
Pertusaria subambigens Dibben
Thallus verrucose or smooth in part, matte or slightly glossy, pale grey, greenish grey or whitish green; apothecia produced in thalline warts, these open and exposing the disc from early in development, crowded, usually with concentric ridges and fissures around the disc, coloured like the thallus or paler 1-2.5 mm wide, the disc usually white-pruinose, pink, yellowish, light green, brown, grey or blackish; hymenium 120-180 µ high, colourless or pigmented grey or brown in upper portions, the pigments K-; spores 8 per ascus, 10-28 × 5-18 µ, with a single wall layer, 2-3 µ thick, the ends not or scarcely bulging into the lumen.
Reactions: Medulla K+ yellow turning red-brown, PD+ orange-red.
Contents: fumarprotocetraric and succinprotocetraric acid, and ± UN4 and protocetraric acid.
Habitat: On conifer twigs and branches in humid, lower to middle elevation forest, shade-tolerant.
Similar Species: Pertusaria ophthalmiza, which has 1-spored asci, may be similar to forms of this species having abundant white pruina on the disc and weakly fissured/ridged thalline warts.
Specimens: Goward 94-915.
Local Status: Uncommon.
Pertusaria sp. 6 sensu Björk
Thallus smooth, waxy, pale greenish grey or creamy whitish; apothecia produced within thalline warts opening by 1, or rarely 2-3 pores, the pores surrounded by a grey halo on the thalline material; hymenium 200-250 µ high, brownish grey in upper portions, the pigment K+ mauve; spores 4-8 per ascus, 40-110 × 20-60 µ, with a 2-layered walls collectively 5-10 µ thick, the inner wall bulging into the lumen, at least at some stages of development.
Reactions: Cortex K+ yellow.
Contents: Unknown
Habitat: On acidic bark of conifers and ericaceous shrubs in cool, humid, lower to middle elevation forest.
Similar Species: See notes under Pertusaria sommerfeltii.
Specimens: Björk 12288, 13179.
Local Status: Occasional.
Notes: Widespread in BC, Idaho and Washington.