Euptelea polyandra

The order Ranunculales consist of seven groups (Figure 2): Papaveraceae, Euptelea, Circaeasteraceae, Lardizabalaceae, Menispermaceae, Berberidaceae, and Ranunculaceae.

With the help of molecular data, several surprising new findings have been made regarding the Ranunculales. First of all, the order does not belong in the Magnoliidae as previously thought. Instead, it is highly supported as a separate order at the base of the "eudicots", a group characterized by tricolpate or tricolpate derived pollen. Other eudicot groups closely related to Ranunculales are Nelumbonaceae, Platanaceae, and Proteaceae (Figure 1).

The second finding which is even more surprising is the relative positions of the families found within the Ranunculales (Figure 2). It had commonly been thought that the Ranunculaceae (buttercup family) was relatively "primitive". Now we know that this family is among the most derived within the Ranunculales, and instead Papaveraceae, Furmariaceae, and Euptelea are among the earliest branching groups.

The third surprise is the inclusion of Euptelea within the Ranunculales. Because of its reduced floral morphology (adapted to wind pollination), this genus had previously been included with the Hamamelidaceae. Molecular data show this genus to be near the base of the Ranunculales, although its exact position is not resolved.

The Hoot lab continues to actively work on the Ranunculales (see research interests). Past and present work were funded by the National Science Foundation

Figure 1. Position of Ranunculales within the "Lower" Eudicots based on atpB, rbcL and 18S sequence data. (Tree adapted from Hoot et al. 1999)

Figure 2. Phylogeny of the Ranunculales, showing relative postions of the major families within this order. Tree is based on atpB, rbcL and 18S sequence data. (Tree adapted from Hoot et al. 1999)


Hoot, S. B. and P. R. Crane. 1995. Inter-familial relationships in the Ranunculidae based on molecular systematics. Plant Systematics and Evolution (Suppl.) 9: 119-131.

Hoot, S. B., S. Magallón, and P. R. Crane. 1999. Phylogeny of basal eudicots based on three molecular data sets: atpB, rbcL, and 18S nuclear ribosomal DNA sequences. Annals of the Missouri Botanical Garden 86: 1-32.

Angiosperm Phylogeny Group (consists of 29 plant systematists, including S. B. Hoot). 1998. An ordinal classification for the families of flowering plants. Annals of the Missouri Botanical Garden 85: 531-567.

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For further information concerning angiosperm (flowering plant) phylogeny