Maple
Acer /ˈeɪsər/ is a genus of trees or shrubs commonly known as
maple. Maples are variously classified in a family of their own, the Aceraceae, or together with the Hippocastanaceae included in the family Sapindaceae. Modern classifications, including the Angiosperm Phylogeny Group system, favour inclusion in Sapindaceae. The type species of the genus is
Acer pseudoplatanus. There are approximately 128 species, most of which are native to Asia, with a number also appearing in Europe, northern Africa, and North America. Only one species, the poorly studied
Acer laurinum, is native to the Southern Hemisphere. Fifty-four species of maples meet the International Union for Conservation of Nature criteria for being under threat of extinction in their native habitat.