The Buttercup Family

FAMILY: RANUNCULACEAE

In strict botanical terms, the family Ranunculaceae, which belongs to the order Ranales (Ranunculales), is generally considered to be the most primitive of all angiosperms - flowering plants. There are about 50 genera (15 British) with around 2,000 species in this family, (The Flora of China states that there are 60 genera and 2,500 species), which is widely distributed in temperate and subtropical regions of both hemispheres, mainly on mountains in the tropics. Most members of this family, however, are found mainly in the colder regions of the world. Many are well-known wild flowers or garden flowers, including buttercups, anemones, delphiniums, hellebores, aquilegias and clematis. Some, particularly Aconitum (monkshood), are poisonous.

Main Characteristics of Ranunculaceae

Members of the family are usually herbaceous, (Xanthorrhiza, however, is a shrub with soft yellow wood), with Clematis being the only climbing/woody genus. The perennial species form a small rhizome or tuber, which develops new roots each year.

Leaves: are usually divided or palmately lobed, but are heart shaped in Ranunculus ficaria (lesser celandine), and narrow and undivided in some species of Ranunculus. They usually arise from the base of the plant, or alternately up the stem, but in Clematis (with the exception of Clematis alternata) they are opposite. Stipules are usually absent, although with stipules in Thalictrum; Actaea and some others, however.

Flowers: may be solitary, but they are often found in clusters or spikes. Sepals usually five, although there may be many, and often petaloid. In many species, there are no proper petals. When petals are present these are ordinarily tubular, and serve as nectaries. In Helleborus and Eranthis, for example, the sepals are large and showy, and petaloid, the petals, quite inconspicuous tubular structures, two-lipped at the mouth. In Caltha, Anemone, Clematis etc., there are no petals at all, the sepals becoming colourful and showy. In Ranunculus, the petals are colourful, and showy while the sepals, quite exceptionally in this family, are small and green. Stamens usually very numerous. Carpels, numerous.

Fruit/seed: a group of achenes, follicles or a berry.