Grammitis wattsii is a fern in the family Polypodiaceae. The specific epithet honours the Reverend W. W. Watts (1856âÂÂ1920), a prominent Australian cryptogamist active in the late 19th and early 20th centuries.
The plant is an epiphytic fern. It has an erect or shortly creeping rhizome with dense, chestnut brown, narrow pointed scales. Its simple fronds combine a 0.5âÂÂ5 cm long stipe with a narrowly elliptic-linear lamina 5âÂÂ20 cm long and 0.4âÂÂ1.2 cm wide.
The fern is endemic to AustraliaâÂÂs subtropical Lord Howe Island in the Tasman Sea; it is confined to the cloud forest on the upper slopes and summits of Mounts Lidgbird and Gower.