Aphylogeny of Ranunculales was published in 2009, based onmolecular phylogenetic analysis ofDNA sequences. The authors of thispaper revised the subfamilies andtribes of the order.[2] This is reflected in the subsequent revision of the APG, APG IV (2016).[3]
The analysis revealed that the order consisted of threeclades, Eupteleaceae, Papaveraceae and a third clade, considered to be the "core" Ranuculales, consisting of the remaining five families. The phylogeny of the families is shown in the cladogram.
The fossil formLeefructus, described in 2011, has been recognized as a member of this order.[4]Leefructus mirus shows fully developed leaves; stem and flower that are very similar in structure to those of the modernbuttercups. The fossil is dated to 125Mya (million years old) and it not only proves that Ranunculales is an ancient group ofeudicots but demonstrates that the wholeangiosperm clade may be older than expected. The structure of the plant and its age may lead to a new approach regarding the field that studies the evolution offlowering plants. The fact thatLeefructus shows a well-developed structure similar to modern ranunculids suggests that this group of eudicots may have developed earlier than the age of the fossil.[citation needed]
Historically the termRanales was used to include the Ranunculaceae and related families, as described byBentham and Hooker. This became replaced with Ranunculales byMelchior in 1964.[citation needed]
In the Cronquist system, the Papaveraceae and Fumariaceae (including the plants in the optional family Pteridophyllaceae) were treated as a separate orderPapaverales, placed in this same subclass Magnoliidae. The Cronquistcircumscription of Ranunculales is now known to bepolyphyletic. Sabiaceae is in a clade of basal eudicots separate from Ranunculales. Coriariaceae is now placed in the orderCucurbitales.[citation needed]
^Magallon, S; Gomez-Acevedo, S; Sanchez-Reyes, LL; Tania Hernandez-Hernandez, T (2015). "A metacalibrated time-tree documents the early rise of flowering plant phylogenetic diversity".New Phytologist.207 (2):437–453.Bibcode:2015NewPh.207..437M.doi:10.1111/nph.13264.PMID25615647.
Wang, Wei; Lu, An-Ming; Ren, Yi; Endress, Mary E.; Chen, Zhi-Duan (January 2009). "Phylogeny and classification of Ranunculales: Evidence from four molecular loci and morphological data".Perspectives in Plant Ecology, Evolution and Systematics.11 (2):81–110.Bibcode:2009PPEES..11...81W.doi:10.1016/j.ppees.2009.01.001.
