Spadix (botany)

In botany, a spadix (/ˈspeɪdɪks/ SPAY-diks; plural spadices /ˈspeɪdɪsiːz/ SPAY-dih-seez, /speɪˈdaɪsiːz/ spay-DY-seez) is a type of spike inflorescence having small flowers borne on a fleshy stem. Spadices are typical of the family Araceae, the arums or aroids. The spadix is typically surrounded by a leaf-like curved bract known as a spathe. For example, the "flower" of the well known Anthurium spp. is a typical spadix with a large colorful spathe.[1]

1. Leaves and Inflorescence of the Arum maculatum, 2. Underground root-stock, 3. Lower part of spathe cut open, 4. Spike of fruits- showing in succession (from below) female flowers, male flowers, and sterile flowers forming a ring of hairs borne on the spadix.

Diagram of spadix

Monoecious aroids have unisexual male and female flowers on the same individual and the spadix is usually organized with female flowers towards the bottom and male flowers towards the top. Typically, the stigmas are no longer receptive when pollen is released which prevents self-fertilization. There are also compound spadix inflorescences, in which the axis is branched. Usually the whole inflorescence is covered by a stiff boat shaped hood, for example the coconut.