A NEW SPECIES OF POTAMOGETON (POTAMOGETONACEAE) FROM THE UNIQUE HABITAT: MONTEZUMA WELL, ARIZONA, U.SA.

摘要

Montezuma Well is a geothermal limnocrene spring within Montezuma Castle National Monument, Yavapai County, Arizona, U.S.A. The Well's unusual geological qualities, water chemistry, and a history of aquatic plant collecting are discussed. Evidence tosupport the fact that a unique species of Potamogetón has likely grown in this location for thousands of years and is now recognized as the seventh apparent autochthonous endemic species from this small area is presented. Although this new species shares a few superficial characters with P. illinoensis Morong, it is easily distinguished by its massive height (7-8 m tall), lack of floating leaves, long acuminate leaf apices of its submerged leaves, and bright translucent green leaf color. A complete description with drawing and photographs is provided.