Lindsaea linearis

Lindsaea linearis is known as the screw fern, as the fronds may have a twisting appearance. It has a creeping stem with fronds that can grow up to 50 cm (20 in) in length.^[1] It is a small fern of widespread distribution in many parts of Australia. Found in a variety of habitats, often near swamps or moist places and by rocks, heathland or open forest.^[2] It has a dark stem, unlike the similar necklace fern, which is green.

Screw fern
Screw fern at Ferndale Park, Chatswood West, Australia
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Division:	Polypodiophyta
Class:	Polypodiopsida
Order:	Polypodiales
Family:	Lindsaeaceae
Genus:	Lindsaea
Species:	L. linearis
Binomial name
Lindsaea linearis Sw.
Synonyms
Adiantum lineare (Sw.) Poir. Lindsaea trilobata Colenso Lindsaea lunata Willd. Lindsaya linearis orth. var. F.Muell.

The screw fern was first described by Swedish botanist Olof Swartz in 1801, and still bears its original name.^[3]