Lecidea
Crustose lichens containing a trebouxioid alga; thallus smooth, scurfy, granular, sorediate, areolate, subsquamulose, or immersed; apothecia with a non-algal rim that may be prominent and persistent, or thin and quickly receding; hymenium formed of straight, mostly unbranched paraphyses, with or without crystals in the upper layer; hypothecium colourless or pigmented; asci clavate, with various types of tholi; spores usually 8 per ascus, sometimes more; spores colourless, elliptic, oblong, or globose, mostly non-septate.
Note: None of the species named here as Lecidea actually belongs to Lecidea sensu stricto, but currently have no genera to house them.
References: Tønsberg 1992; Printzen & Tønsberg 1999; Foucard 2001; Spribille 2006; Spribille & Printzen 2007; Printzen et al. 2008; Spribille & Björk 2008.
| 1a. | Thallus sorediate; all chemical spot tests negative …2 |
| 2a. | Thallus UV-, containing pseudoplacodiolic acid, greyish white, or pale blue, usually slightly brownish, soralia erumpent from the substrate and becoming confluent/leprose; soredia individually 10-30 µ and often clumped; apothecia common, black and often with a bluish pruina, strongly convex; spores 6-12 × 2-4.5 µ …Lecidea leprarioides |
| 2b. | Thallus UV+ white or blue-white, lacking pseudoplacodiolic acid, colour various; soralia arising from a surficial thallus, usually remaining distinct; soredia and apothecia various …3 |
| 3a. | Prothallus usually lacking; soredia 20-40 (‑50) µ wide, reddish brown with olive or blue-gray mottled; apothecia red-brown; spores 9-18 × 6-8 µ; thallus containing lobaric acid; locally common on bark, usually close to the ground …Myochroidea porphyrospoda |
| 3b. | Blue-black hypothallus usually conspicuous, sometimes only on the margins of the thallus; soredia 20-30 µ wide, rarely with reddish brown tones; apothecia colour various; spores either globose, or mostly narrower; thallus lacking lobaric acid; habitat various, but most often well above ground level …4 |
| 4a. | Soredia white or yellowish, arising from yellowish green areoles; apothecia dark grey to blackish; spores 9-15 × 4-7 µ …Lecidea pullata |
| 4b. | Soredia silvery grey to blackish or brown; apothecia red-brown to blackish; spores globose, 4-7 µ wide …Lecidea nylanderi |
| 1b. | Thallus lacking soredia; sometimes with positive chemical spot tests …5 |
| 5a. | Spores (8‑) 12-100 per ascus; hypothecial hyphae tending to be vertically oriented, the walls at least slightly pigmented; asci with a dark blue tube in the well-thickened tholus (like Porpidia-type) …6 |
| 6a. | Disc quickly becoming botryoid, with numerous segments at maturity; rim inconspicuous, rapidly receding; apothecia matte or waxy, not glossy; spores 12-100 per ascus …7 |
| 7a. | Apothecia dark brown to black; hypothecial hyphae with dark brown pigments in the walls, individually easily seen, K+ reddish; spores (12‑) 50-100 per ascus, (3‑) 4-6.5 × (1‑) 1.8-2.5 µ …Lecidea morula ined. |
| 7b. | Apothecia medium to dark red-brown; hypothecial hyphae with orange-brown pigments in the walls, individually difficult to discern, K+ deep orange; spores (8‑) 12-16 per ascus, 7.5-11 × (2‑) 3-5 µ; to be sought …[Lecidea coriacea Spribille ined.] |
| 6b. | Discs simple, or seldom with 2-3 segments; rim thin, but conspicuous and persistent well into maturity; apothecia glossy or waxy, not matte; spores 8-16 per ascus, of various size …8 |
| 8a. | Apothecia 0.3-1.2 mm wide; apothecia usually glossy; rim (at least on young apothecia) darker than the disc, at least at the apex; spores 7-10 (‑12) × 3-5 µ; mostly on wood or rough bark …Lecidea cf. exsequens |
| 8b. | Apothecia 0.2-0.5 (‑0.7) mm wide; rim distinctly paler than the disc; apothecia usually waxy; spores 6-14 × 2-6 µ; mostly on smooth bark, especially on ericaceous shrubs, rare on wood …Lecidea betulicola |
| 5b. | Spores 8 per ascus; hypothecial hyphae haphazardly arranged, the walls lacking pigments; asci various …9 |
| 9a. | Hypothecium conspicuously darker than the hymenium; lower half of the hymenium densely oil-inspersed; spores often citriform (broadly rounded on the sides and more or less pointed at the tips), 9-15 × 5-6 µ …Lecidea albofuscescens |
| 9b. | Hypothecium pale, not conspicuously darker than the hymenium …10 |
| 10a. | Thallus of olive, grey-white, brown to red-brown squamules, apothecia with a thick, persistent rim; spores mostly 10-13.5 × 5-6.5; to be sought …[Myochroidea leprosula (Arnold) Printzen, Spribille & Tønsberg] |
| 10b. | Thallus not producing squamules; apothecia and spores various …11 |
| 11a. | Spores globose to very broadly elliptical, 3.5-10 × 3.5-7 µ …12 |
| 12a. | Spores of globose to broadly elliptical shapes intermixed; thallus areolate, P+ orange-red …13 |
| 13a. | Spores 6-10 × 4-7 µ; thallus K+ yellow; apothecia 0.3-0.8 mm wide, dark grey-brown to blackish; rim quickly receding; common on acidic bark …Lecanora fuscescens |
| 13b. | Spores 4.5-9 × 6-7 µ; thallus K+ yellow; apothecia 0.5-1 mm wide, orangish to reddish brown or blackish; rim smooth to wavy, receding late; to be sought …[Lecidea paddensis (Tuck.) Zahlbr.] |
| 12b. | Spores always globose, 3.5-6 µ wide; thallus areolate or immersed, PD- or + orange-red …14 |
| 14a. | Thallus immersed to thickly areolate, P-; exciple with abundant, tiny POL+ crystals; apothecia black, with a persistent, often glossy rim, sometimes becoming highly undulate and irregularly shaped; uncommon …Lecidea antiloga |
| 14b. | Thallus of surficial areoles, P+ orange-red; exciple POL-; apothecia medium to dark grey-brown, rarely black, round, never undulate; common on acidic bark …Lecanora boligera |
| 11b. | Spores elliptical, if broadly so, then thallus P- …15 |
| 15a. | Thallus immersed or very inconspicuous, lacking a black prothallus; spores up to 4.5 µ wide and 12 µ long …16 |
| 16a. | Apothecia creamy whitish, lacking any distinct pigment layer within; spores 7-15 × 2-2.5 (‑3) µ wide; common and widespread …Lecidea albohyalina |
| 16b. | Apothecia medium to dark red- or grey-brown, to dark brown or black, with at least one distinctly pigmented layer within …17 |
| 17a. | Spores 7-12 × 2.8-3.2, about half with 1 septum; upper hymenium with brown pigments, not bluish, greenish, grey or reddish …Lecidea improba ined. |
| 17b. | Spores mostly wider than in 17a, most simple, very few or none 1-septate; upper hymenium either red-brown or bluish, greenish, or grey-brown …18 |
| 18a. | Apothecia deep red-brown, lacking pruina, with an indistinct rim, even when young; upper hymenium with deep red-brown pigments; spores 6-8 × 3-4.5 µ, always lacking septae …Lecidea rubrocastanea |
| 18b. | Apothecia dark grey or black, usually grey-pruinose, with a distinct rim, at least when young; upper hymenium with bluish, greenish, or grey-brown pigments; spores 6-12 × 2.5-4.5 µ, with a few 1-septate spores intermixed …Lecidea turgidula |
| 15b. | Thallus relatively conspicuous, not immersed, sometimes outlined by a black prothallus; spores various, but mostly larger than in 15a …19 |
| 19a. | Thallus dark green to khaki green, thickly areolate; rim usually quickly receding; spores 9-14 × 4-7 µ; to be sought in dry forests …[Lecidea holopolia (Tuck.) Zahlbr.] |
| 19b. | Thallus thick or thin, but brownish grey or creamy whitish; apothecial rim thick or thin, but persistent, the apothecia constricted at the base, not adnate; spores various …20 |
| 20a. | Thallus brownish grey to whitish, thickly areolate; apothecial rim thick, conspicuous and persistent; disc and rim not particularly translucent when wet; spores 11-15 × 5-8 µ; growing on acid-bark shrubs, conifers, and moss/detritus in subalpine to alpine habitats …Myochroidea rufofusca |
| 20b. | Thallus whitish, smooth, scurfy and thin; apothecial rim thin but persistent; disc and rim translucent when wet; spores 9.5-12.5 × 3.8-4.5 µ; growing on trunks of old Populus trichocarpa, sometimes also on other nutrient-rich bark …Lecidea erythrophaea |
Lecidea albofuscescens Nyl.
Thallus whitish or grey green, thin, sometimes warty or granular; apothecia individually widely scattered, 0.3-0.6 mm, the rim persistent and prominent, glossy brownish black, coloured like the disc rather than the thallus, the disc flat, glossy; rim lacking algae, opaque dark brown throughout, even under the hypothecium; hymenium 45-60 µ high, colourless, cotaining abundant oil droplets, at least when young; upper hymenium medium to dark brown (rarely blue-violet or red-brown), lacking granules; hypothecium dark brown, blackish brown or dark red-brown; paraphyses 1-1.5 µ wide at mid point; spores 1-celled, broadly elliptical with blunt or rounded ends, mixed with at least a few having pointed ends (lemon-shaped), 9-15 × 3-5 µ.
Reactions: Thallus K- or K+ yellow.
Contents: No known lichen substances in typical forms.
Habitat: Bark and wood surfaces of conifers and Betula papyrifera, sometimes rain-sheltered or in dripzones, lower to middle elevations.
Similar Species: No other epiphytic crust species in the study area has an exciple that is dark pigmented throughout.
Specimens: Björk 13229, 13230.
Local Status: Common.
Lecidea albohyalina (Nyl.) Th. Fr.
Thallus greenish grey or whitish, smooth and inconspicuous or with few small areoles; apothecia unevenly scattered and a few clustered, 0.1-0.3 mm wide, the rim inconspicuous and quickly receding, the disc strongly convex to subspherical; rim non-algal, formed of rather sparse hyphae, the lumina of which (especially at the margins) are broad and elliptical; hymenium 35-50 µ high, colourless; epihymenium lacking pigments and granules; hypothecium colourless; asci Biatora-type, 8-spored; spores narrowly elliptical, 1-celled or a few with a single crosswall, 7-15 × 2-3 µ.
Reactions: All spot tests negative.
Contents: No known lichen substances.
Habitat: on various bark surfaces, and on mosses over bark. All forested elevations.
Similar Species: See notes under Biatora meiocarpa.
Specimens: Björk 10891.
Local Status: Occasional.
Lecidea antiloga Stirt.
Thallus of thin areoles 0.3-1 (‑1.5) mm wide, pale grey or brownish grey, or, more often, immersed and not apparent; apothecia 0.2-0.4 mm wide, black or brownish black, round or of irregular shapes, with a thin but persistent and prominent, non-algal rim having the colour and texture like the disc, the disc flat or slightly concave; exciple colourless within, but dark brown or bluish green in the outermost layer, these pigments K+ greenish, also containing minute POL+ crystals; hymenium 35-60 µ high, dark brown, with a layer of fine granules on the top and dark olive or blackish in upper layers, K+ greenish; hypothecium colourless; asci similar to Bacidia-type; paraphyses more or less straight, often branching near the tip, with a pigment sheath and swollen up to 3.5 µ at the tip; spores spherical, 3.5-6 µ wide.
Reactions: All spot tests negative.
Contents: No known lichen substances.
Habitat: On hard-weathered wood, elsewhere reported to grow on bark. Creek margin, at lower elevation.
Similar Species: Macroscopically similar to a number of species having black apothecia and a non-algal rim, but the spherical spores are distinctive. Lecanora boligera has similarly sized, spherical spores, but has a well developed thallus and usually has much paler apothecia lacking granules.
Specimens: Björk 12866.
Local Status: Rare.
Lecidea betulicola (Kullh.) H. Magn.
Thallus pale grey, thin or occasionally lumpy; apothecia 0.3-0.7 mm wide, brownish grey, dull or waxy, with a thin but long-persisent rim that is usually paler than the disc; rim formed of radiating hyphae, light grey-brown, IKI+ lavender-purple; upper hymenium light grey-brown, K- except clearing and loosening; hypothecium colourless or light grey-brown, any pigments in the hyphal walls, the hyphae tending to be vertically oriented, at least in portions leading up to the asci, K- except clearing; asci more or less Porpidia-type, IKI+ blue with a darker blue tube extending the entire length of the apical thickening; spores 8-16 per ascus, elliptical, non-septate, 6-14 × 2-6 µ.
Reactions: All spot tests negative.
Contents: No lichen substances.
Habitat: Mostly on smooth bark of ericaceous shrubs, less often on conifer bark, lower to (especially) upper forested elevations.
Similar Species: Lecidea exsequens is probably closely related. It differs in its habit of growing on wood or rough bark rather than smooth bark, in having larger, glossier apothecia, and an IKI- exciple.
Specimens: Björk 10807, 12860, 13181.
Local Status: Common.
Notes: A common local form consistently has 8 spores per ascus (forma octospora Spribille ined.). Our polysporous material has been attributed to forma endamylea, which is distinguished by its IKI+ lavender exciple.
Lecidea erythrophaea Flörke ex Sommerf.
Thallus smooth or cracked, pale grey or greenish grey, matte, often scurfy, sometimes immersed; apothecia 0.25-0.75 (‑1) mm wide, dark reddish brown or reddish black, somewhat translucent when wet, with a non-algal rim having the colour and texture of the disc, the rim thin or thick, but quickly receding, the disc shallowly concave when young, but becoming flat to low-convex; rim interior pigmented red-brown or orangish brown in outher portions, lacking crystals; hymenium 35-55 µ high, colourless except pigmented red-brown or orangish brown in uppermost portions, lacking granules, the paraphyses slightly gnarled, a few branched and anastomosing; asci similar to Bacidia-type; spores 8.5-11.5 × 3.5-4 µ, broadly elliptical to elliptic-fusiform, simple.
Reactions: All spot tests negative.
Contents: No known lichen substances.
Habitat: On high-pH bark, especially Populus trichocarpa (cottonwood) trunks, and on conifer twigs in cottonwood dripzones, always in humid habitats. Lower elevation forests.
Similar Species: Forms with blackish apothecia may appear similar to Lecidea albofuscescens, and the two grow in similar habitats, but L. albofuscescens has an oil-inspersed hymenium and dark pigments throughout the exciple.
Specimens: Björk 9870, 12375, 13964.
Local Status: Occasional.
Lecidea cf. exsequens Nyl.
Thallus whitish, thin and granular, or immersed; apothecia 0.3-1.2 mm wide, glossy as if polished, light grey-brown or tan, with a thin, receding rim that is usually darker than the disc; exciple formed of radiating hyphae, light brown, IKI-; upper hymenium light brown, K- except clearing and loosening; hypothecium colourless or light brown, any pigments concentrated in the hyphal walls, the hyphae tending to be vertically oriented, at least where they lead up to the asci, K- (except clearing) or K+ olive; asci more or less Porpidia-type, IKI+ blue with a darker blue tube extending the entire length of the apical thickening; spores (8‑) 12-16 per ascus, elliptical, 7-10 (‑12) × 3-5 µ.
Reactions: All spot tests negative.
Contents: Unknown.
Habitat: On wood or rough bark of conifers, lower to (especially) upper forested elevations.
Similar Species: See notes under Lecidea betulicola.
Specimens: Björk s.n. (Edgewood West), hb. Björk.
Local Status: Uncommon.
Notes: Local specimens’ identity with Lecidea exsequens is questionable (fide Zdeněk Palice).
Lecidea improba Björk ined.
Thallus smooth or areolate, grey or green-gray, inconspicuous, or, more often, immersed and not apparent; apothecia 0.3-0.7 mm wide, grey-brown, dark brown or blackish, with a thin, receding rim, the rim interior and exterior lacking crystals; hymenium 35-45 µ high, lacking crystals, light to medium brown or olive brown in upper portions; spores 7-12 × 2.6-3.2 µ, elliptical or oblong, about half with a septum.
Reactions: All spot tests negative.
Contents: Unknown.
Habitat: On Thuja twigs. Lower elevations.
Similar Species: Lecidea albofuscescens may appear similar macroscopically and lives in similar habitat, but has a densely oil-inspersed hymenium and simple spores.
Specimens: Goward 96-1256.
Local Status: Rare.
Notes: Known only from the study area.
Lecidea leprarioides Tønsberg
Thallus immersed, sending up large quantities of granular soredia that may cover the entire surface, often multicoloured olive, grey and brown; soredia 10-30 µ, granular, hygrophilic; apothecia common, blackish grey and often with light dusting of grey pruina, 0.2-0.5 mm wide, the rim coloured like the disc, thin and quickly receding, the disc high-convex to subspherical; rim non-algal; hymenium 30-45 µ high, light to medium brownish blue-green (pigment K+ green); upper hymenium with variable pigmentation, blue-green, purplish, olive or brownish, usually K+ green, also with granules that clear in K; hypothecium colourless; spores mostly 1-celled, 6-12 × 2-4.5 µ.
Reactions: All spot tests negative.
Contents: Pseudoplacodiolic acid.
Habitat: Decorticated branches of conifers, and on Picea twigs in rain-shedding foliar cone, lower to middle elevations.
Similar Species: No other species in the study area has diffuse granular soredia arising from an immersed crust on decorticated branches. Lecidea turgidula is similar but lacks soredia.
Specimens: Björk 12064.
Local Status: Very common.
Lecidea morula Björk & Spribille ined.
Thallus whitish, smooth or granular, or (less often) immersed; apothecia 0.3-1 (‑1.5) mm wide, dark brown or black, matte, with a thin and quickly receding rim, becoming lumpy with age and often splitting into multiple convex discs separated by thin sterile portions; rim black, formed of radiating, linear hyphae; hypothecium dark brown, the pigments concentrated in the hyphal walls, the hyphae strongly vertically oriented and easily seen individually, K+ reddish brown; hymenium dark brown in lower portions, grading into light brown upwards, K+ reddish brown; asci more or less Porpidia-type, IKI+ blue with a darker blue tube extending the entire length of the apical thickening; spores about 50-100 per ascus, seldom as few as 12, elliptical or spindle-shaped (3‑) 4-6.5 × (1‑) 1.8-2.5 µ.
Reactions: Thallus K- or K+ yellow.
Contents: Unknown.
Habitat: On soft wood of conifer snags, less often on logs, within or just above the winter snowpack. Lower to (especially) upper forested elevations.
Similar Species: Lecidea coriacea is very similar, but usually has fewer spores per ascus, and lighter, K+ deep orange pigments in the red-brown apothecia. These two species are probably related to Lecidea betulicola and Lecidea exsequens.
Specimens: Goward 96-1140.
Local Status: Rare.
Notes: So far known only from inland BC.
Lecidea nylanderi (Anzi) Th. Fr.
Thallus of areoles that rather quickly disintegrate into soredia, both the areoles and the soredia silvery bluish grey, all usually subtended by a blue-black hypothallus; soredia granular, 20-30 µ, tightly grouped into aggregates up to 70 µ wide; apothecia uncommon, 0.3-0.9 mm wide, medium to dark red-brown, the margin thin but rather persistent, the disc flat to low-convex; rim non-algal; hymenium 45-50 µ high, colourless or pale brownish; upper hymenium reddish brown, the pigment unchanged in colour, but more diffuse in K; hypothecium colourless; spores 1-celled, spherical, 4-7 µ wide.
Reactions: All spot tests negative.
Contents: Divaricatic acid.
Habitat: Bark on old Pseudotsuga and Betula papyrifera trunks, less often on branches or snags of Pseudotsuga, lower to middle elevations.
Similar Species: Lecidea pullata has finer soredia and usually grows on decaying bark of broadleaf shrubs.
Specimens: Björk 10800, 12389; Goward 01-225.
Local Status: Common.
Lecidea pullata (Norman) Th. Fr.
syn. Lecidea amaurospoda (Anzi) Vainio
Thallus grey-brown or olive, areolate, the areoles disintegrating into fine soredia 20-30 µ wide, usually with a blue-black, non-algal prothallus between the areoles and outlining the margins of the thallus; apothecia usually absent, 0.3-1.2 mm wide, dark grey or bluish black, with a thin, receding rim; upper hymenium, hypothecium and rim olive-gray to greyish blue-green; paraphyses not swollen at the tip; spores thick-walled, 9-15 × 4-7 µ.
Reactions: UV+ white.
Contents: Sphaerophorin, and minor amounts of isosphaeric acid.
Habitat: On smooth or somewhat rough bark of conifers and, especially deciduous shrubs, usually within the winter snowpack. All forested elevations.
Similar Species: See notes under Lecidea nylanderi.
Specimens: Goward 01-226.
Local Status: Common.
Lecidea rubrocastanea Spribille & Printzen
Thallus of patchy areoles, sometimes cracked where dense, or immersed in part, olive-brown or olive green; apothecia individually scattered or in small clusters, 0.25-0.45 (‑0.7) mm wide, matte or sometimes glossy, reddish brown to reddish black, the rim thin, quickly receding, formed of cylindrical hyphae arrayed fan-like as seen in cross section; hymenium 35-55 µ high, colourless except in uppermost portions, where the gel is pigmented light to medium reddish brown, also with medium to dark brown pigments in the paraphysis wall at the tip; hypothecium colourless; spores 8 per ascus, simple, broadly elliptical, 6-8 × 3.5-4.
Reactions: Spot tests all negative.
Contents: No known lichen substances.
Habitat: On conifer bark and wood, most often on branches, in dry, open forest. Lower to middle elevations.
Similar Species: Japewia tornoensis appears very similar, but has glossier higher-convex apothecia and larger spores with thick walls.
Specimens: Björk 10768.
Local Status: Uncommon.
Lecidea turgidula Fr.
Thallus immersed, not visible, or with a few greenish grey granules at the surface; apothecia 0.2-0.5 mm wide, individually scattered or a few clustered, the rim thin and quickly receding, coloured like the disc, the disc blackish blue-green or blackish brown, lightly dusted with blue-gray pruina, high-convex or subspherical; rim non-algal, formed of closely packed, fanning hyphae; hymenium 30-45 µ high, pale to light grey-green, K+ greener; upper hymenium medium to dark bluish grey-green, heavily granular, K+ greener and granules clearing; hypothecium colourless or pale to medium brown; spores 1-celled or a few with a single crosswall, oblong to elliptic, 6-12 × 2.5-4.5 µ.
Reactions: Thallus spot tests all negative.
Contents: No known lichen substances.
Habitat: On a conifer snag and decorticated branches of Pinus contorta. All forested elevations.
Similar Species: Lecidea leprarioides is similar, but has soredia.
Specimens: Björk 13209, 13942.
Local Status: Uncommon.