Grammitis

Grammitis is a genus of ferns in the family Grammitidaceae, within the order Polypodiales. The genus comprises a large number of species, most of which are small, delicate ferns that grow as epiphytes in tropical and subtropical forests.

Distribution and habitat: Grammitis ferns are widespread in tropical and subtropical regions around the world, with diverse communities in Australasia, Southeast Asia, the Caribbean, and the Americas. They are commonly found as epiphytes on tree trunks and branches, or as lithophytes on rocks, in humid, shaded forests from sea level to montane zones.

Description: Members of Grammitis are typically small, with simple to shallowly pinnate or even undivided fronds. The fronds are often narrow and delicately structured. Rhizomes are creeping, and many species bear delicate scales. Sori occur in the sori on the undersides of the fronds and are often located along the veins or at the margins, sometimes protected by a reflexed leaf margin forming a false indusium.

Taxonomy: Grammitis is the type genus of Grammitidaceae. The group has undergone revisions as molecular phylogenetics has clarified relationships within Grammitidoideae; several species formerly placed in Grammitis have been transferred to related genera by some classifications. As a result, species counts and circumscription vary among sources.

Ecology and conservation: As epiphytes in humid forests, Grammitis species depend on stable moisture and air circulation. Many are not well-known outside fern enthusiasts, but habitat loss and collection threaten some species, particularly those with restricted ranges in montane forests.