Grammitis (dwarf polypody) is a genus of ferns in the family Polypodiaceae, subfamily Grammitidoideae, according to the Pteridophyte Phylogeny Group classification of 2016 (PPG I). It had formerly been placed in the family Grammitidaceae, but this family is no longer recognized by most authors because phylogenetic analyses of DNA sequences have shown that it is embedded in Polypodiaceae.

The delimitation of Grammitis was drastically narrowed in the first decade of the 21st century. It now contains about 25 species. In 2003, a study of the distribution of grammitid ferns placed 11 species in the New World, 7 in Africa, and 4 in the Pacific.

The genus Grammitis was established by Olof Swartz around 1801. (sources vary on the exact date). The name is derived from Greek, gramma, grammatos meaning "a line or thread" and refers to the arrangement of the sori in some species. The type species for Grammitis is Grammitis marginella.

The only known fossil of a grammitid fern has been named Grammitis succinea, but it is not clear that it belongs to Grammitis as more recently defined. It was found in Oligocene amber from the Dominican Republic.

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