Pellaea

Pellaea
Pellaea andromedifolia
Scientific classification
Kingdom:	Plantae
Division:	Pteridophyta
Class:	Polypodiopsida
Order:	Polypodiales
Family:	Pteridaceae
Subfamily:	Cheilanthoideae
Genus:	Pellaea Link[1]
Type species
Pellaea atropurpurea (L.) Link
Species
See text.
Synonyms
Cheilosoria Trevis. Choristosoria Mett. ex Kuhn Ormopteris J.Sm. Pellaeopsis J.Sm. Pteridella Mett. ex Kuhn Synochlamys Fée[1]

Pellaea is a genus of ferns in the Cheilanthoideae subfamily of the Pteridaceae.^[2] The genus name is derived from the Greek word πελλος (pellos), meaning "dark," and refers to the bluish-gray stems.^[3] Members of the genus are commonly known as cliffbrakes.^[4] They primarily grow in rocky habitats, including moist rocky canyons, slopes, and bluffs.^[3]

Distribution

They are most abundant and diverse in the southwestern United States south into Andean South America, central and southern Africa, and eastern Australia to New Zealand.

Description

They typically have creeping rhizomes and pinnately to bipinnately compound leaves lacking prominent scales or trichomes on the blades. Like most members of Pteridaceae, they have marginal sori protected by a false indusium formed from the reflexed leaf margin.

The distinction of Pellaea from the typically hairier or scalier Cheilanthes has proven difficult, with some members (e.g., the African P. viridis) being of uncertain affinity, listed by different authors in both genera. Furthermore, Pellaea contains a number of sections that may warrant generic status since they appear to represent convergence in phenotypes related to arid habitats rather than similarity due to common descent. These sections are:

• Pellaea section Pellaea: includes most American members of the genus as well as a single African member (P. rufa);
• Pellaea section Ormopteris: includes three or four South American species in or near Brazil;
• Pellaea section Platyloma: includes the Australian and New Zealand species;
• Pellaea section Holcochlaena: includes the African species.

Members of the genus are not generally used for any commercial purpose, although several species (most notably P. rotundifolia and P. falcata of section Platyloma) are cultivated as indoor plants.

Species

Pellaea section Pellaea Pellaea atropurpurea (L.) Link – purple-stem cliffbrake Pellaea brachyptera (T.Moore) Baker – Sierra cliffbrake Pellaea breweri D.C.Eaton – Brewer's cliffbrake Pellaea bridgesii Hook. – Bridges' cliffbrake Pellaea glabella Mett. ex Kuhn – smooth cliffbrake Pellaea mucronata (D.C.Eaton) D.C.Eaton – birdfoot cliffbrake Pellaea wrightiana Hook. – Wright cliffbrake Pellaea truncata Goodding – spiny cliffbrake Pellaea ovata (Desv.) Weatherby – ovateleaf cliffbrake Pellaea section Ormopteris Pellaea cymbiformis

Pellaea section Platyloma Pellaea paradoxa R.Br. (Hook.) Pellaea rotundifolia (G.Forst.) Hook. Pellaea falcata (R.Br.) Fée Pellaea calidirupium Pellaea nana Pellaea section Holcochlaena Pellaea calomelanos Pellaea dura Pellaea viridis (Forssk.) Prantl – green cliffbrake Pellaea boivinii[4][5]

References

1. "Genus: Pellaea Link". Germplasm Resources Information Network. United States Department of Agriculture. 2007-10-05. Retrieved 2011-11-05.
2. Christenhusz, Maarten J. M.; Zhang, Xian-Chun; Schneider, Harald (18 February 2011). "A linear sequence of extant families and genera of lycophytes and ferns" (PDF). Phytotaxa. 19: 7–54. ISSN 1179-3163.
3. Windham, Michael D. "Pellaea Link, Fil. Spec. 59. 1841.". Flora of North America. eFloras.org. Retrieved 2011-11-05.
4. "Pellaea". Integrated Taxonomic Information System. Retrieved 2011-11-05.
5. "GRIN Species Records of Pellaea". Germplasm Resources Information Network. United States Department of Agriculture. Retrieved 2011-11-05.

External links

• USDA PLANTS Profile