The fern genus Dryopteris (Dryopteridaceae) in Ascension and Saint Helena islands, Atlantic Ocean

Abstract

The fern genus Dryopteris (Dryopteridaceae) in the isolated Atlantic Ocean islands, Ascension and St Helena is reviewed. Three species are known from these islands. Dryopteris ascensionis is endemic to and the only Dryopteris species known from Ascension Island. This species now appears to be extinct since has not been recorded since 1975, and was not found during repeated searches in the 1990s. Two Dryopteris species, D. cognata and D. napoleonis, are endemic to St. Helena and are rare on that island. Dryopteris napoleonis is lectotypified.