What is "pellaea"

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