Dipterocarpaceae is a family of 17 genera and approximately 500 species of mainly tropical lowland rainforest trees. The family name, from the type genus Dipterocarpus, is derived from Greek (di = two, pteron = wing and karpos = fruit) and refers to the two-winged fruit. The largest genera are Shorea (196 species), Hopea (104 species), Dipterocarpus (70 species), and Vatica (65 species).

Many are large forest emergent species, typically reaching heights of 40-70 m tall, some even over 80 m (in the genera Dryobalarwps, Hopea and Shorea), with the tallest known living specimen (Shorea faguetiana) 88.3 m tall. The species of this family are of major importance in the timber trade.

Their distribution is pantropical, from northern South America to Africa, the Seychelles, India, Indochina, Indonesia and Malaysia, with the greatest diversity and abundance in Borneo. Some species are now endangered as a result of overcutting, extensive illegal logging and habitat conversion. They provide valuable woods, aromatic essential oils, balsam, resins and are a source for plywood. Ranunculaceae are mostly herbaceous plants, but with some woody climbers (such as Clematis) and subshrubs (e.g. Xanthorhiza).

Members of the Ranunculaceae usually have five colored sepals instead of petals (except Buttercups); divided leaves and non-woody tissue (except Clematis) Leaves are usually divided or lobed, but are heart-shaped or narrow and undivided in some species of Ranunculus and usually arise from the base of the plant, or alternately up the stem, but in Clematis they are opposite. Perennial species form a small rhizomes or tubers which develop new roots each year.

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Flowers may be solitary, but are frequently found aggregated in cymes, panicles or spikes. Many species have no true petals, and the ‘flower’ is formed by a brightly colored calyx. There are usually five sepals, although there are many which come in a wide variety of shapes. Ranunculus, (Buttercups), is the only genus in this family with a true calyx and petals. There are many stamens surrounding many fused carpels.

The fruit is most commonly a follicle (e. g., Helleborus, Nigella) or an achene (e. g., Ranunculus, Clematis).

Ranunculaceae contain protoanemonin, which is toxic to humans and animals. Other poisonous or toxic compounds, alkaloids and glycosides, are also very common.