Flowering Plant Families, UH Botany

Rosidae: Apiales. The Araliaceae are mostly tropical shrubs and trees comprising about 70 genera and 700 species. The leaves are alternate or rarely opposite, palmately or pinnately compound or more than once compound or rarely simple; stipules are usually present and liguliform or adnate to the petiole and sheathing. The flowers are actinomorphic and most frequently unisexual, often in heads or umbels. The perianth is biseriate but the calyx is reduced to usually 5 minute teeth or a seamlike rim adnate to the ovary. The corolla consists mostly of 5-10 usually more or less distinct, usually valvate petals arising from a nectary disk on the summit of the ovary. The stamens are distinct, usually as many as and alternating with the petals. The gynoecium consists of a single compound pistil of 2-15 carpels, an equal number of styles or these connate into one style, and an inferior ovary with 2-15 locules, each bearing a single pendulous, axile ovule. An epigynous nectary disk is generally confluent with the enlarged stylar base or stylopodium. The fruit is a berry or drupe that sometimes splits into one-seeded segments.

Tetraplasandra sp., 'ohe. Note the umbellate inflorescences and pinnate leaves in this Hawaiian endemic.

Tetraplasandra sp., 'ohe. Note the umbellate inflorescence and flowers with five and six petals and alternating stamens in this endemic Hawaiian species. The inferior ovary and nectary disk are also evident in this photo.

Reynoldsia sandwicensis, 'ohe. In this endemic Hawaiian species the petals are often connate in pairs or threes, giving the appearance of commonly 4 or 5 petals. There are usually about 10 stamens.

Cheirodendron platyphyllum, 'olapa. This Hawaiian endemic species has leaves that quake like aspen.

Munroidendron racemosum. This is a rare Hawaiian endemic genus that has the flowers in racemes instead of the usual umbels found in the family.

Arthrophyllum sp. Note the palmately compound leaf, 5-merous flowers, umbellate inflorescence and the calyx that forms a rim with minute teeth around the summit of the inferior ovary.

Schefflera actinophylla, octopus tree. This ornamental species from Australia has flowers with about a dozen perianth segments and stamens. The petals fall away that is, are caducous as the stamens expand. A conspicuous disk is present and a style is lacking.