### Identification Commonly known as a "Strap Lichen," *Ramalina celastri* is a fruticose (shrubby) lichen that forms tufted, pendulous clumps on tree bark. Look for flattened, leathery branches—called thalli—that range in color from a pale celadon green to a dusty sea-foam grey. Unlike its close relatives, this species usually lacks powdery white spots (soredia). Instead, the most striking field mark is the presence of "apothecia": small, tan-colored fruiting discs that resemble miniature saucers with a thin green rim, often clustered near the tips or along the margins of the straps.
### Habitat & Range This species is a sun-lover, frequently found in open woodlands, coastal scrubs, and parklands across the Southern Hemisphere, particularly in Australia, New Zealand, and parts of Africa. It avoids the deep, damp shade of closed canopies, preferring the well-lit outer branches of isolated paddock trees or the wind-swept edges of forests where air circulation is high.
### Behaviour To the casual observer, *R. celastri* appears static, but it is a master of "resurrection." During dry spells, it enters a state of dormancy, becoming brittle and pale to survive desiccation. However, the moment a mist rolls in or rain falls, the lichen rapidly rehydrates, turning pliable and vibrant as it restarts its biological clock. It grows at a glacial pace, often adding only a few millimeters to its length each year.
### Diet As a symbiotic organism, *R. celastri* doesn't "eat" in the traditional sense. It is a partnership between a fungus (the architect) and a green alga (the chef). The alga performs photosynthesis, converting sunlight into sugars to feed the pair, while the fungus provides the physical structure and harvests essential minerals and moisture directly from the atmosphere and passing dust.
### Fascinating Fact *Ramalina celastri* is a living "canary in the coal mine." Because it absorbs all its nutrients directly from the air, it is incredibly sensitive to atmospheric pollutants like sulfur dioxide. If you find a tree draped in healthy, lush tufts of this lichen, you can be certain you are breathing some of the cleanest, most pristine air on Earth!