Clinging Snakefern

Clinging Snakefern, Microgramma species, is a genus of small epiphytic ferns in the family Polypodiaceae found in tropical and subtropical forests of the Americas, from Florida and the Caribbean through Central America to South America. The ferns cling tightly to tree bark and rock surfaces using creeping rhizomes with specialized clinging scales, making them true epiphytes that depend entirely on the host surface for physical support while deriving all their water and nutrients from rainfall and atmospheric deposition. The common name 'snakefern' refers to the slender, creeping rhizomes that resemble snakes threading through moss and bark. The fronds are small and simple, either entirely fertile bearing sori on their undersurface or sterile with entire margins. Clinging snakeferns contribute to the high epiphyte diversity of tropical forest canopies and are important components of the moss-and-lichen matrix on tree trunks in humid forests. They are sensitive to moisture availability and desiccation and are among the first species to decline when humid forest is cleared or fragmented. Several Microgramma species are used as ornamental plants in warm-climate gardens for their ability to creep over rocks and tree stumps. Conservation status varies by species within the genus.