Microsorum pteropus 'Narrow' grown on mangrove wood. Microsorum pteropus is a highly variable species, and new varieties are easily bred. Microsorum pteropus 'Narrow' has narrower leaves, which grow at a less acute angle from the stem than the normal Microsorum pteropus. Leaves becomes 10-20 cm and a rhizome from 10-15 cm or more. The plant