Flowering Behavior of the Neotropical Genus Anthurium (Aracae)

The genus Anthurium (Araceae) is one of the most taxonomically complex genera in the neotropics. Studies of living material have shown modes of behavior which probably have a direct influence on pollination biology and evolution. Separation of the sexes is generally accomplished by marked protogyny. Considerable differences also exist in the rate of development of flowers, the presence, source and amount of stigmatic nectar, as well as the method of pollen presentation. The genus exhibits an unusual pattern of staminal emergence. In all species studied, the lateral pair of stamens are first to emerge, usually one at a time, followed by the anterior, then the posterior stamens of the alternate pair. There are also differences in the degree of exsertion, the disposition with respect to the stigma, degree of retraction and changes in pollen color. Some species have stamens which are retracted completely after opening; others have stamens which scarcely emerge but instead force the pollen out in long ribbons. Important differences also exist in flower aromas with both fly and bee pollination syndromes exhibited. All of these aspects of flowering behavior are natural phenomena believed to be important in pollination biology