common frullania liverwort clasping bark in dark reddish mats
- Size
- Width: 2–5 cm
- Lifespan
- 3–7 years
- Diet
- Grows on bark of trees, rocks, and wood in damp, shaded forests. Requires consistent moisture, high humidity, and stable bark surfaces. Prefers rough bark of native trees in old-growth forest with stable microclimate.
- Habitat
- Grows on the bark of trees, on rocks, and on wood throughout New Zealand. A creature of the bark, the trunk, the places where the tree is old and the surface is rough. Forms tiny, leafy, creeping mats that hug the bark in neat, obsessive lines.
- Range
- Found throughout the North and South Islands on bark of native and introduced trees, rocks, and wood in damp, shaded forests. Most common in lowland and montane forests with high rainfall. Also found in temperate regions worldwide.
- Endemism
- Native
- Main Threats
- None significant. This species is common and widespread in damp, shaded forests. Localised threats include forest clearance, removal of old trees, and climate change reducing forest floor moisture.
- Population
- Not Threatened. Common frullania is common on the bark of native and introduced trees throughout New Zealand, particularly in damp, shaded forests. It is a widespread species found in temperate regions around the world.
- Conservation Status
- Not Threatened
The one that looks like it has OCD has stems that are creeping and branching, forming dense, leafy mats on the bark. The leaves are tiny, less than a millimetre long, and are arranged in two rows along the stem, overlapping like roof tiles. Each leaf is divided into two lobes: a large, rounded dorsal lobe that lies flat against the bark and a smaller, inflated ventral lobe (a water sac) that sticks out like a tiny balloon. The colour is dark green to reddish-brown, often with a metallic sheen. It is the liverwort of the neat line, the one that grows in obsessive, orderly rows.
What makes it special are the water sacs. Common frullania is a leafy liverwort, and it has a unique feature. Each leaf has a smaller, inflated lobe (the water sac) that is shaped like a tiny helmet or balloon. These water sacs help the plant retain moisture, storing water for dry periods. They also give the plant its distinctive, bumpy texture when viewed under a hand lens. It is the liverwort of the water balloon, the one that carries its own water supply.
The leaves are arranged in two rows along the stem, with the dorsal lobes lying flat against the bark and the ventral lobes sticking out to the sides. The result is a neat, overlapping pattern that looks like a tiny, green mosaic or a piece of obsessive geometry. Under a microscope, the pattern is mesmerising, each leaf perfectly positioned, each water sac precisely inflated.
Biologically, the common frullania reproduces by spores, released from capsules on short stalks. It also reproduces asexually via gemmae, tiny buds that break off and grow into new plants. This dual strategy allows it to colonise new patches of bark quickly, spreading across the tree trunk like a slow, green tide.
To find common frullania is to find the tiny, leafy mats on the tree bark. They are dark green, tidy, and obsessive, a living geometry on the trunk. You need a hand lens to see the water sacs, the tiny balloons, the neat rows of overlapping leaves. It is the liverwort of the neat line, the one that grows in obsessive, orderly rows, the one that makes the bark look like it has been paved with tiny green tiles.