R. Fraley

Candelaria (Candleflame Lichen)

Candelaria concolor

(and close relatives in genus Candelaria)

Lemon-yellow, powdery thallus that glows against bark year-round.
Tiny leaflike lobules and granular soredia form bright cushions; minute yellow discs (apothecia) may dot mature patches.

Candleflame lichen on birch Candleflame lichen on birch
Powdery yellow soredia and tiny lobes hugging the bark.
A typical patch of Candelaria concolor showing its granular, lemon-yellow surface on sunlit bark.
Size: 4170×2780

Camera: Canon EOS 5D Mk IV
Lens: EF 100mm f/2.8 Macro USM
Settings: ISO 800 • Aperture f/11 • Shutter 1/4 s

Description

Candelaria is a small foliose/squamulose lichen. The thallus is bright yellow to yellow-green (usnic-acid rich), composed of tiny overlapping lobules with a powdery (sorediate) surface. Apothecia, when present, are flat yellow discs with a matching rim. Common on deciduous bark, fence rails, and nutrient-enriched substrates; often intermixed with greenshields and other crustose yellows.

Close view of apothecia and soredia Close view of apothecia and soredia
Tiny yellow discs (apothecia) among powdery soredia.
Note the lecanorine yellow rims and the flour-like reproductive dust that gives the species its soft texture.
Size: 4170×2780

Camera: Canon EOS 5D Mk IV
Lens: EF 100mm f/2.8 Macro USM
Settings: ISO 800 • Aperture f/11 • Shutter 1/6 s

Behavior

Ecology & growth: A photobiont-fungus partnership that spreads by soredia (powdery fragments) and spores from apothecia. Tolerant of light exposure and mild urban enrichment; patches expand slowly along bark ridges.

Color

Brilliant lemon-yellow to yellow-green; can appear brighter after rain. Underside pale; no distinct rhizines.

Morphology

Minute lobules (0.2–1 mm) with granular soredia; margins often fringed by tiny lobes.

Substrate

Most frequent on deciduous tree bark (maple, ash, elm, birch), twigs, wooden rails; rare on rock.

Size

Patch size from a few millimeters to several centimeters; individual lobules sub-millimetric. Apothecia typically 0.2–1.5 mm across.

Images

Community with greenshield and red-fruited Cladonia Mixed lichen community
Candelaria alongside greenshield (*Flavoparmelia*) and red-fruited *Cladonia*.
Shows how Candelaria occupies sunny bark patches within diverse colonies.
Size: 4170×2780

Camera: Canon EOS 5D Mk IV
Lens: EF 100mm f/2.8 Macro USM
Settings: ISO 800 • Aperture f/11 • Shutter 1/5 s

Sorediate cushions on twig Sorediate cushions on twig
Powdery reproduction gives a soft, matte surface.
Compact cushions on a sun-exposed twig—classic candleflame color and texture.
Size: 4170×2780

Camera: Canon EOS 5D Mk IV
Lens: EF 50mm f/2.5 Compact Macro
Settings: ISO 400 • Aperture f/8 • Shutter 1/60 s

Tiny apothecia detail Apothecia detail
Minute yellow discs with matching rims.
A focus-stacked view to show the fruiting bodies used for spore production.
Size: 4170×2780

Camera: Canon EOS 5D Mk IV
Lens: EF 100mm f/2.8 Macro USM
Settings: ISO 800 • Aperture f/8 • Stacked 8 frames

Habitat context on maple trunk Habitat context on maple trunk
Bright yellow patches on nutrient-enriched bark in partial sun.
Wide environmental frame showing distribution around knots and bark fissures.
Size: 4170×2780

Camera: Canon EOS 5D Mk IV
Lens: EF 50mm f/2.5 Compact Macro
Settings: ISO 200 • Aperture f/8 • Shutter 1/40 s

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