Polystichum

Taxobox
name = "Polystichum"

---

image_width = 220px
image_caption = "Polystichum setiferum"
regnum = Plantae
divisio = Pteridophyta
classis = Pteridopsida
ordo = Dryopteridales
familia = Dryopteridaceae
genus = "Polystichum"
genus_authority = Roth
subdivision_ranks = Species
subdivision = See text.

"Polystichum" is a genus of about 180 species of ferns with a cosmopolitan distribution. The highest diversity is in eastern Asia, with about 120 species in China alone; Africa (17 species), North America (15 species), and Europe (5 species) have much lower diversity.

Many ferns of this genus have stout, slowly-creeping rootstocks that form a crown, with a vase-like ring of evergreen fronds 30-200 cm long. The sori are round, with a circular indusium. The stipes have prominent scales. The genus differs from "Dryopteris" in the indusium being circular, not reniform, and in having stronger, more persistent fronds with a harder, somewhat rough, texture.

Hybridisation is frequent in the genus, with several named hybrids.

Several species are grown as ornamental plants in gardens.

"Polystichum" species are used as food plants by the larvae of some Lepidoptera species including "Pharmacis fusconebulosa".

elected species

;Selected hybrids
*"Polystichum × bicknellii" ("P. aculeatum" × "P. setiferum")
*"Polystichum × illyricum" ("P. aculeatum" × "P. lonchitis")
*"Polystichum × lonchitiforme" ("P. lonchitis" × "P. setiferum")

External links

* [http://ucjeps.berkeley.edu/cgi-bin/get_JM_treatment.pl?19,31 Jepson Manual Treatment]