frullania liverwort clinging to bark in dark overlapping scales
- 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 in damp, shaded forests throughout New Zealand. A creature of the bark, the trunk, the places where the tree is old and the surface is rough. Forms tiny, overlapping, leafy mats that cling to the bark in dense, almost obsessive patterns, a miniature mosaic of green and reddish-brown with geometric precision. The liverwort of the obsessive pattern, the one that covers the bark in tiny, repeating tiles.
- Range
- Found throughout the North and South Islands on bark of native 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 humidity.
- Population
- Not Threatened. Frullania liverwort is common on the bark of native trees, on rocks, and on wood in damp, shaded forests throughout New Zealand. It is a widespread species found in temperate regions around the world.
- Conservation Status
- Not Threatened
The one that covers the bark in tiny tiles 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. The leaves are so densely packed that the stem is completely hidden, creating a smooth, tiled surface that looks almost manufactured. It is the liverwort of the obsessive pattern, the one that covers the bark in tiny, repeating tiles.
What makes it special is the pattern. Frullania liverwort has one of the most intricate, obsessive patterns of any liverwort in New Zealand. The leaves are arranged in perfect, overlapping rows, each leaf a tiny tile in a living mosaic. The pattern is so regular, so precise, that it looks like it was designed by a machine. Under a hand lens, the pattern is mesmerising, each leaf perfectly positioned, each water sac precisely inflated. It is the liverwort of the obsessive detail, the one that covers the bark in a living quilt, the one that makes the tree trunk look like it has been paved with tiny green and brown tiles.
The water sacs (ventral lobes) are the key to the plant's survival. They store water, allowing the liverwort to survive dry periods. When the air is damp, the sacs are plump and round. When it is dry, they shrink, conserving moisture. The sacs also give the mat its bumpy texture, a landscape of tiny hills and valleys.
Biologically, the frullania liverwort 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.
To find frullania liverwort is to look at the bark of an old tree. There it is, a dense, leafy mat of tiny, overlapping leaves, dark green to reddish-brown, covering the bark in obsessive, repeating patterns. You need a hand lens to see the individual leaves, the water sacs, the perfect geometry. It is the liverwort of the obsessive pattern, the one that covers the bark in tiny, repeating tiles, the one that proves that nature loves geometry as much as any mathematician.