Pellaea (plant)
Pellaea is a genus of ferns in the Cheilanthoideae subfamily of the Pteridaceae. The genus name is derived from the Greek word πελλος, meaning "dark," and refers to the brown stems. Many members of the genus are commonly known as cliffbrakes. They primarily grow in rocky habitats, including moist rocky canyons, slopes, and bluffs.
Distribution
Ferns in this genus 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
These ferns 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 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 ;
- Pellaea section Platyloma: includes the Australian and New Zealand species;
- Pellaea section Holcochlaena: includes the African species.
Most members of the genus are not generally used for any commercial purpose, although several species are cultivated as indoor plants.
Species
, the Checklist of Ferns and Lycophytes of the World recognized the following species:- – coffee cliffbrake
- – purple-stem cliffbrake
- – Sierra cliffbrake
- – Brewer's cliffbrake
- – Bridges' cliffbrake
- – hot rock fern
- – heart-leaved cliffbrake
- – sickle fern
- – Gastony's cliffbrake
- – smooth cliffbrake
- – P. bridgesii × P. mucronata
- – Intermediate cliffbrake
- – Lyngholm's cliffbrake
- – birdfoot cliffbrake
- – dwarf sickle fern
- – ovate-leaved cliffbrake
- – button fern
- Ternate-leaved cliffbrake
- – spiny cliffbrake
- – green cliffbrake
- Wright's cliffbrake