Actinostachysminuta, a new species of grass fern from Mindanao, Philippines

Actinostachysminuta Amoroso & Coritico (Schizaeaceae), from Mindanao, Philippines, is described herein as a new species. This species is distinguished from all other species of Actinostachys (grass ferns) by its notably short and narrow fronds, distinct triangular stipe, and bifid apex of the sorophore lamina with profuse white long hairs. This species is distinct from the other known Philippine species of Actinostachys by its diminutive epiphytic habit and a habitat restricted to the trunks of the tree fern Sphaeropterispolypoda (Baker) R.M.Tryon. A taxonomic key to the species of Philippine Schizaeaceae that incorporates the new species is provided.