Teloschistes chrysophthalmus

Family: Teloschistaceae

Golden-eye Lichen (Teloschistes chrysophthalmus) is a bright orange to yellow-green, shrubby lichen that grows on bark in open, sunlit habitats. It is distinctive for its upright, branching form and the abundant, vivid orange apothecia that resemble tiny eyes scattered across the thallus.

For representative images and visual context, see the page: Golden-eye Lichen in the Gallery section.

Description

Teloschistes chrysophthalmus is recognized by:

Growth form: fruticose
Thallus: yellow-green to orange, slender, tufted, and somewhat wiry
Lobes: narrow, irregularly branching, often with fine cilia along margins
Surface features: generally smooth, lacking soredia or isidia
Underside: not differentiated (radially symmetrical branches)
Attachment: attached at a single base point, projecting outward

Colonies form small, bushy tufts that stand away from the substrate rather than lying flat. It most often occurs on bark, especially on exposed branches and trunks where light is abundant.

Substrate and Habitat

Typical substrates and settings include:

Bark, often on deciduous trees in open areas
Occasionally on shrubs or small branches

Notes may include:

Strong preference for full sun or high light exposure
Common in open woodlands, edges, and isolated trees
Often found as scattered tufts rather than dense mats

Identification

Key features for field diagnosis:

Color: yellow-green to bright orange, intensifying in strong light
Form: small, shrubby, tufted growth projecting outward from bark
Surface: smooth branches, often with fine cilia
Underside: not applicable (fruticose structure)
Reproductive structures: abundant orange apothecia with thallus-colored margins
Chemistry: typically K+ purple (anthraquinones present)

This species is distinguished by its combination of fruticose growth and numerous orange apothecia. It differs from Xanthoria species, which are foliose and closely appressed to the substrate. It may be confused with other Teloschistes species, but T. chrysophthalmus typically shows conspicuous, eye-like apothecia and a relatively robust, tufted habit.

Ecology and Notes

Often associated with nutrient-enriched environments, including areas influenced by bird perches or agricultural activity
Tolerant of moderate nitrogen levels and may indicate localized enrichment
Occurs sporadically in Minnesota but can be locally abundant in suitable habitats
Research Grade observations support its identification where well-developed apothecia are present

References

Consortium of Lichen Herbaria
https://lichenportal.org
Lichens of North America (Brodo et al.)
https://www.lichen.com
iNaturalist taxon page
https://www.inaturalist.org/taxa/127104-Teloschistes-chrysophthalmus