Ranunculaceae

[4][5] The sepals, petals, stamens and carpels are all generally free (not fused), the outer flower segments typically number four or five.

[10] The fruits are most commonly free, unfused achenes (e.g. Ranunculus, Clematis) or follicles (e.g. Helleborus, Eranthis, Nigella), but a berry in Actaea.

Contact with plant sap may cause inflammation and blistering of the skin, while ingestion can cause irritation of the mouth, vomiting, and diarrhea.

[12] David, (2010)[13] placed the Ranuculaceae, together with the Eupteleaceae, Lardizabalaceae, Menispermaceae, Berberidaceae, and Papaveraceae in the Ranunculales, the only order in the superorder Ranunculanae.

[16] Early subdivisions of the family, such as Michel Adanson (1763), simply divided it based on one-seeded or many-seeded fruit.

Tamura's complete system was structured as follows; The genus Glaucidium, having been moved to its own family (Glaucidiaceae), has since been restored to Ranuculaceae.

The position of Glaucidium and some of its unique morphological characteristics prompted Stevens to suggest that it be given subfamilial rank as the monotypic Glaucidioideae.

In recent years, researchers have used nuclear genes (obtained through transcriptome sequencing technology) to further investigate the phylogenetic relationships of the Ranunculaceae family, and their findings are consistent with those of Wang and colleagues (2009).

However, this study indicates that the ancestors of the Ranunculaceae family experienced multiple whole-genome duplication (WGD) events, which may be related to the longstanding prosperity of this ancient group.

[21] The Early Cretaceous Leefructus mirus from the Yixian Formation in China was described as belonging to the "compare Family stem lineage to the Ranunculaceae".

[22] The oldest confirmed representative of the family is Paleoactaea nagelii Pigg & DeVore described on the basis of fruits coming from the Upper Paleocene of North Dakota.

Many genera are well known as cultivated flowers, such as Aconitum (monkshood), Clematis, Consolida (larkspur), Delphinium, Helleborus (Christmas rose), Trollius (globeflower).