Christopher H. Haufler

Polypodium appalachianum is a fern species native to eastern North America. Sometimes called the Appalachian polypody or Appalachian rockcap fern, it is very similar in appearance to Polypodium virginianum. For years, P. virginianum—long considered a variety of the British Polypodium vulgare—was recognized as having cryptic races, with diploid, triploid, and tetraploid representatives. Since the triploid specimens bore abortive spores, it was apparently the hybrid between the diploid and tetraploid groups. In 1991, it was resolved that the type of P. virginianum was the tetraploid series, and

Bommeria elegans is a species of ferns, native to Mexico.

Cystopteris utahensis, commonly called the Utah bladderfern is a rare species of fern found in canyons and on sheltered cliff faces with calcareous rocks. It mainly grows on the Colorado Plateau in the western United States, but is also found in a few locations in southern New Mexico and an adjacent area of Texas. Studies of its genetics show that it originates from a natural hybrid of the species Cystopteris bulbifera and Cystopteris reevesiana.

Visit the page for more details.

Visit the page for more details.