Orchids are the largest family of flowering plants with more than 26,000 species. Orchids have among the smallest seeds of all flowering plants, the typical orchid seed is the size of a speck of dust. The small size of the seeds is achieved at the expense of embryo and endosperm, the latter not developing in orchids. A mature orchid seed consists of an extremely small and simplified embryo in the shape of a spherical cluster of cells enclosed in a single cell layer thick seed coat. The seed coat forms a balloon around the embryo, a clear adaptation to wind dispersal.

An orchid seed capsule may contain millions of seeds, as in the case of the tropical American orchid Cycnoches chlorochilon, which produces almost four million seeds. Spargere questo gran numero di semi al vento aumenta le possibilità che alcuni finiscano su un ospite compatibile in un luogo adatto alla germinazione.

Foto: Cultivar Phalaenopsis di Nicolas Perrault II