Lecania
Crust lichens containing a trebouxioid alga; thallus areolate, granular, squamulose, or immersed; apothecia with an algal rim or a non-algal rim, resembling the thallus or the disc in colour and texture; non-algal rim formed of rounded cells; algal rim formed of cylindrical hyphae or rounded cells; hymenium often granular in upper parts, formed of mostly simple, stout paraphyses often swollen at the tips and that are embedded in gel; hypothecium colourless or pale brownish; asci clavate, with a thickened tholus that reacts IKI+ medium blue with a darker blue conical lining on a pale axial mass; spores 8-16 per ascus, colourless, 1-3 septate, oblong, elliptical or rarely fusiform, with thin walls, sometimes curved.
References: van den Boom & Ryan 2004; Reese-Naesborg 2008.
| 1a. | Many or all spores with 3 septae …2 |
| 2a. | Epihymenium conspicuously granular; apothecia matte, often 2-toned pinkish and grey; spores 12-20 × 3-6 µ, often more than 8 per ascus, usually straight; paraphyses often swollen to 5 µ wide at the tips …Lecania fuscella |
| 2b. | Epihymenium lacking granules or granules few and scattered; apothecia pale to light tan-pink, glossy or translucent; spores 15-19 × 4-5 µ, 8 per ascus, usually curved; paraphyses swollen to only about 3 µ at the tip …Lecania naegelii |
| 1b. | Spores all 1-septate …3 |
| 3a. | Spores mostly simple …4 |
| 4a. | Spores 8.5-10 × 2-3 µ; apothecial rim with few or no algae; growing on bark, usually above the winter snowpack …Lecania cyrtellina |
| 4b. | Spores 9-11 × 3-4 µ; apothecial rim with a distinct algal layer; growing on mosses over trunks within the winter snowpack …Lecania muscicola ined. |
| 3b. | Spores 1-septate …5 |
| 5a. | Spores mostly curved, bean-shaped; usually on smooth bark of Populus tremuloides trunks and branches …Lecania dubitans |
| 5b. | Spores mostly straight, elliptic or fusiform …6 |
| 6a. | Paraphyses not swollen at the tips; the terminal cell always cylindrical …Lecania prasinoides |
| 6b. | Paraphyses distinctly swollen at the tips, the terminal cell elliptical or globose …7 |
| 7a. | Growing in sites that are persistently humid and slow to dry, usually growing within the winter snowpack; apothecia pale pink light to medium brown, distinctly translucent when wet …Lecania madida |
| 7b. | Growing in sites that are quick to dry, growing above the average winter snowpack; apothecia pale to dark brown, orangish brown or reddish brown, not or scarcely translucent when wet; widely misreported in the region, but to be sought …[Lecania cyrtella (Ach.) Th. Fr.] |
Lecania cyrtellina (Nyl.) Sandstr.
Thallus smooth or verruculose, inconspicuous, pale green or whitish; apothecia pale pink to medium brown, sometimes mottled, 0.25-0.5 mm wide, with a thin, receding rim containing few or no algae, the disc low- to high-convex; hymenium 30-40 (‑45) µ high, colourless or with a pale brownish pigment in upper portions, the paraphyses with the uppermost cell usually distinctly swollen, some to 5 µ wide; hypothecium colourless; spores 8-12 (‑15) × 2-3 (‑4) µ, mostly simple and a few 1-septate spores intermixed.
Reactions: Spot tests all negative.
Contents: No known lichen substances.
Habitat: On nutrient-rich bark in humid places slow to dry, often with Lobaria or Nephroma. Lower elevations.
Similar Species: Lecania cyrtella is similar, but has orangish or reddish brown apothecia, larger spores, and a higher hymenium.
Specimens: Björk s.n. (2 January, 2006), hb. Björk.
Local Status: Unknown.
Lecania dubitans (Nyl.) A.L. Sm.
Thallus scurfy, white or pale grey, thin and continuous, often several thalli converging into large patches; apothecia individually scattered over the thallus or a few clustered, 0.2-0.4 mm wide, the rim algal, thin and inconspicuous, eventually disappearing, the disc dark brown or blackish brown, usually low-convex, sometimes becoming more domed and constricted at the base; hymenium 45-55 µ high, colourless; upper hymenium medium to dark brown, lacking granules or with calcium oxalate over the surface; hypothecium colourless, the layer below containing abundant algae; paraphyses rather stout, about 2 µ thick at midpoint, the apex swollen to 3-5 µ wide; spores oblong, mostly curved, 2-celled with a very thin crosswall, usually filled with abundant, small, even-sized granules, at maturity, 12-17 × 4-6 µ.
Reactions: All spot tests negative.
Contents: No known lichen substances.
Habitat: Smooth bark of Populus tremuloides (aspen), mostly on the trunks; rarely on bark of other trees or shrubs in aspen drip-zones, lower to middle elevation forests.
Similar Species: Arthonia patellulata also grows on smooth bark of Populus tremuloides, and produces a similar-appearing thallus and apothecia. A close look at the apothecia of A. patellulata reveals that unlike L. dubitans, it has no rim. Of the two, L. dubitans is far more common in the study area.
Specimens: Björk 10786.
Local Status: Very common.
Lecania fuscella (Schaerer) Körber
Thallus thin, verrucose or smooth in parts, sometimes with granules or areoles, not scurfy, whitish to pale grey-brown; apothecia mostly clustered, often densely crowded, 0.4-0.8 mm wide, the algal rim thin and quickly receding, the proper rim sometimes prominent but never raised, visible as a paler ring around the disc, the disc low-convex to subspherical, distinctly constricted at the base, light pink-brown or orange-brown, often mottled greyish, sometimes with a light dusting of pruina; hymenium 50-70 µ high; upper hymenium pale to medium red-brown, often granular on the surface; hypothecium colourless, the layer below containing abundant algae; paraphyses rather stout, 2-2.5 µ wide at midpoint, swollen to 3-5 µ wide at the apex; spores elliptical-fusiform or oblong-elliptic, with 3 thin septae, usually filled with tiny, abundant, even-sized granules at maturity, 12-18 × 4-6 µ.
Reactions: All spot tests negative.
Contents: No known lichen substances.
Habitat: Populus tremuloides (aspen) twigs, and twigs of Abies in aspen dripzone. Lower elevations.
Similar Species: Somewhat like Lecania naegelii, which lacks algae in the rim or nearly so.
Specimens: Björk 15197.
Local Status: Rare.
Lecania madida Reese-Naesborg & Björk
Thallus verruculose or granular, or smooth in part, pale green or greyish white; apothecia pinkish white or light to medium brown or reddish brown, distinctly translucent when wet, finely mottled with darker pigment spots, the rim thin and receding, the disc becoming convex; hymenium 45-55 µ high, with scattered spots of brown or red-brown pigments in upper portions, the paraphyses with the terminal cell distinctly swollen, some to 5.5 µ wide; spores 10.5-12.5 × 3.2-3.8 µ, 1-septate.
Reactions: Spot tests all negative.
Contents: No known lichen substances.
Habitat: On nutrient-rich bark in humid, slow-to-dry microhabitats, usually within the winter snowpack, lower to middle elevations.
Similar Species: Lecania cyrtella and L. prasinoides are very similar, but the former has more opaque, often darker apothecia and grows mostly on thin, decaying bark of shrubs above the winter snowpack, and the latter has non-swollen paraphysis apical cells.
Specimens: Spribille & Björk 15828.
Local Status: Common.
Notes: The type specimen originated from the study area.
Lecania muscicola Björk ined.
Thallus granular, verruculose, or in part smooth, pale green or greyish green; apothecia 0.2-0.35 mm wide, pale pinkish, with a thin, quickly receding rim containing a distinct algal layer, distinctly translucent when wet, lacking pigment spots; hymenium 30-45 µ high, colourless, the paraphyses with the apical cell distinctly swollen up to 5 µ wide; hypothecium colourless; spores 9-11 × 3-4 µ, most simple, a few 1-septate.
Reactions: Spot tests all negative.
Contents: Unknown.
Habitat: Growing over mosses at the base of Populus tremuloides trunk. Lower elevations.
Similar Species: Lecania prasinoides and L. madida are not known to grow on moss, and have consistently 1-septate spores. Lecania cyrtellina grows only on bark, and has narrower spores.
Specimens: Björk 17830.
Local Status: Common.
Notes: Known only from the study area.
Lecania naegelii (Hepp) Diederich & v. d. Boom
Thallus smooth, scurfy, granular or verruculose, inconspicuous, pale greyish green, pale tan-gray, or whitish; apothecia 0.2-0.6 (‑0.8) mm wide, whitish, grey pinkish, reddish brown, dark brown or black, often mottled, with a thin, quickly receding rim that lacks algae, or has a few clusters of algae in lower portions; hymenium (45‑) 50-65 µ high, colourless or green, grey or brown in upper portions, lacking crystals; spores oblong to elliptical or fusiform-elliptical, 14-20 × 4-5.5 µ, often somewhat curved, 1- to 3-septate.
Reactions: Spot tests all negative.
Contents: No known lichen substances.
Habitat: On bark of aspen and cottonwood (Populus) branches. Lower elevations.
Similar Species: Cliostomum griffithii may have similarly coloured apothecia, but it has a more prominent and persistent rim and conspicuous black pycnidia.
Specimens: Björk 13677.
Local Status: Rare.
Lecania prasinoides Elenkin
Thallus thin, areolate, cracked or granular, or smooth in part, inconspicuous, brownish or greenish-brown; apothecia pale to medium pink, orange or brown, distinctly translucent when wet, lacking darker mottling, the rim thin and receding, containing a distinct algal layer; hymenium 45-55 µ high, colourless or with diffuse red-brown pigments in upper portions, the paraphyses not swollen at the tips; hypothecium colourless; spores 10.5-12.5 × 3-3.8 µ, 1-septate.
Reactions: Spot tests all negative.
Contents: No known lichen substances.
Habitat: On nutrient-rich bark in humid forests, in slow-to dry microhabitats. Lower elevations.
Similar Species: Lecania madida is very similar, but has distinctly swollen paraphysis tips. Lecania cyrtella has apothecia that are not or scarcely translucent when wet, and grows in drier microhabitats above the winter snowpack.
Specimens: Björk 12348.
Local Status: Unknown.