Subclass:
Hamamelidae
Links to Family Pages:
Betulaceae Fagaceae Platanaceae Cannabaceae Hamamelidaceae Ulmaceae Casuarinaceae Juglandaceae Urticaceae Cecropiaceae Moraceae Cercidiphyllaceae Myricaceae
Subclass consisting of 26 families, and about 3,400 species of angiosperms - often referred to as the Amentiferae, or wind-pollinated group. The Hamamelidae are defined by a suite of characters correlated with wind pollination (anemophily): generally woody and deciduous; more or less strongly reduced, unisexual flowers that are borne in catkins; smooth pollen; and nut-like fruits with one or few seeds.
All recent evidence (fossil and morphological/molecular phylogenetic studies) indicate that the Hamamelidae are completely unnatural - with this syndrome of characters evolving independently several times. Most Hamamelidae now belong to various lineages of the Rosidae or to a basal grade of "eudicots" called the "lower hamamelids."