gold dust lichen dusting bark and rock with bright yellow powder
- Size
- Width: 2–10 cm
- Lifespan
- 10–30 years
- Diet
- Grows on bark of trees, rocks, and wood in open, sunny locations. Requires clean air, stable bark surfaces, and good light. Tolerates sun, wind, and moderate drought. Prefers rough bark of native and introduced trees in open, exposed sites.
- Habitat
- Grows on bark of trees, rocks, and wood in open, sunny locations. Forms bright yellow, powdery crust that looks like spilled sunlight.
- Range
- Found throughout the North and South Islands on bark of trees, rocks, and wood in open, sunny locations. Most common on native and introduced trees in urban and rural areas. Also found in temperate and tropical regions worldwide.
- Endemism
- Native
- Main Threats
- None significant. This species is common and widespread in open, sunny locations. Localised threats include removal of old trees, air pollution, and bark disturbance.
- Population
- Not Threatened. Chrysothrix gold dust lichen is common and widespread in New Zealand, particularly on the bark of native and introduced trees in open, sunny locations. Its bright colour makes it easy to spot.
- Conservation Status
- Not Threatened
The one that looks like a splash of yellow paint has a body that is a powdery, granular crust that grows on the surface of the bark or rock, forming a bright yellow to golden-yellow patch. It has no structure, no lobes, no discs, just a fine, dusty layer of yellow granules. It looks like someone spilled sunlight on the bark and forgot to wipe it up. It is the lichen of the golden splash, the one that brings a little bit of sunshine to the darkest forest, the one that is impossible to miss.
What makes it special is the colour. Chrysothrix gold dust lichen is one of the brightest lichens in New Zealand. Its vivid yellow colour stands out against the grey bark, visible from a distance. The colour comes from a pigment called calycin, which acts like a sunscreen, protecting the algae from intense sunlight. The more sun, the brighter it gets. In the shade, it fades to a pale, greenish-yellow. It is the lichen of the sunny spot, the one that loves the light, the one that only shows its true colours in the full glare of the sun.
The chrysothrix gold dust lichen is a crustose lichen, or rather, it is a leprose (powdery) lichen, with no organised structure. Its body is a loose aggregation of powdery granules (soredia), each granule containing a few algal cells wrapped in fungal hyphae. It reproduces by these granules breaking off and blowing away to start new colonies. It is the lichen of the dusty reproduction, the one that scatters its children to the wind.
Biologically, the chrysothrix gold dust lichen is a partnership, a fungus and an alga living together. The fungus provides what little structure there is. The alga provides food through photosynthesis. The bright yellow pigment protects the alga from intense sunlight.
To find chrysothrix gold dust lichen is to find the yellow splash on the bark. It is bright, powdery, and sunny, a little piece of sunshine on the tree. You cannot miss it. It is the lichen of the golden dust, the one that looks like someone spilled sunlight and left it, the one that proves that the most visible things are often the most beautiful.