Proteales

The representatives of the Proteales can be very different from each other due to their very early divergence. They possess seeds with little or no endosperm. The ovules are often atropic.

The oldest fossils of Proteales are of the nelumbonaceous genus Notocyamus from the Barremian stage of the Early Cretaceous of Brazil, 126–121 Ma (million years ago). According to molecular clock calculations, the lineage that led to Proteales split from other plants about 128 Ma or 125 Ma.

Families

Within the classification system of Rolf Dahlgren, the Proteales were in the superorder Proteiflorae, also called Proteanae; The APG II system (of 2003) also recognizes this order, placing it in the clade Eudicots, with the following circumscription:

• order Proteales

• family Nelumbonaceae
• family Proteaceae [+ family Platanaceae]

with "+ ..." = optionally separate family (that may be split off from the preceding family).

The APG III system of 2009 followed this same approach, but favored the narrower circumscription of the three families, firmly recognizing three families in Proteales: Nelumbonaceae, Platanaceae, and Proteaceae. The Angiosperm Phylogeny Website, however, suggests the addition of Sabiaceae, which the APG III system did not place in any order in the eudicots, would be sensible.

The APG IV system of 2016 added family Sabiaceae to the order.

Well-known members of the Proteales include the proteas of South Africa, the banksia and macadamia of Australia, the planetree, and the sacred lotus. The origins of the order are clearly ancient, with evidence of diversification in the mid-Cretaceous, roughly over 100 million years ago. Of notable interest is the family's modern distribution; the Proteaceae is predominantly a Southern Hemisphere family, while the Platanaceae and Nelumbonaceae are Northern Hemisphere plants.