About Callicladium haldanianum (Grev.) H.A.Crum
Callicladium haldanianum, a species of moss, has stems that grow between 3 and 8 centimetres long. Its small cortical cells are defined by thick walls. It has only a small number of pseudoparaphyllia, and clusters of smooth rhizoids grow just below where its leaves attach to the stem. The leaves of this moss are densely packed, arranged in an upturned homomallous pattern, especially toward the ends of branches. The leaves stay concave even when dried, and measure roughly 1 to 2 millimetres long by 0.5 to 0.8 millimetres wide. Key distinguishing features of this moss are its concave leaves, short double costa, curved nearly erect capsules, and sword-shaped, shortly tapered, somewhat flattened branches. In the wild, Callicladium haldanianum grows in a wide range of habitats including logs, stumps, conifer and hardwood forests, tree bases, soil, and rocks. It forms extensive flat or loose mats that tend to crowd out other plant species. It is distributed across multiple Canadian provinces, U.S. states, Europe, and Asia. Because it has low maintenance needs and attractive appearance, Callicladium haldanianum is popular as a plant for terrariums. It grows well in moist conditions and prefers indirect sunlight, which makes it a good choice for indoor environments.
