spleenwort n : any of various chiefly rock-inhabiting ferns of the genus Asplenium

Asplenium is a genus of about 700 species of ferns, often treated as the only genus in the family Aspleniaceae, though other authors consider e.g. Hymenasplenium separate. A few species are occasionally placed in the separate genera Camptosorus, Ceterach and Phyllitis, but these species can form hybrids with other Asplenium species and because of this are usually included in a more broadly defined Asplenium. Some classifications elevate the Aspleniaceae to an order Aspleniales.

Common names include spleenwort (many species), bird's-nest fern (A. nidus and several allied species), with a few other distinct names applied to well-known individual species.

Uses

Both the scientific name and the common name "spleenwort" are derived from an old belief, based on the doctrine of signatures, that the fern was useful for ailments of the spleen, due to the spleen-shaped sori on the backs of the fronds. "-wort" is an ancient English term that simply means "plant" (compare German -wurz).

A few of these ferns have some economic importance in the horticulture trade. The bird's-nest ferns (A. nidus and several very similar, closely related species) are commonly found for sale as a house plant. The Australian Mother Spleenwort (A. bulbiferum is sometimes available at greenhouses, and is of interest, along with the related A. viviparum, for the many small bulblets borne on the fronds that may grow into new plants. This characteristic is also shared with the eastern North American Walking Fern (A. rhizophyllum) and several Mexican species including A. palmeri. The Ebony Spleenwort A. platyneuron is also sometimes sold in nurseries as a hardy plant. However, many spleenworts are epipetric or epiphytic and difficult to cultivate.

Asplenium species are used as food plants by the larvae of some Lepidoptera species including Batrachedra bedelliella which feeds exclusively on A. nidus. For diseases of Asplenium, see List of foliage plant diseases (Polypodiaceae).

Selected species

See also

• Mount Asplenium
• Phyllocladus aspleniifolius (Celery-top Pine, a conifer with Asplenium-like leaves)