Mesangiospermae (core angiosperms) is a cladeofflowering plants (angiosperms), informally called "mesangiosperms". They are one of two main groups of angiosperms. It is a name created under the rules of the PhyloCode system of phylogenetic nomenclature.[1] There are about 350,000 species of mesangiosperms.[2] The mesangiosperms contain about 99.95% of the flowering plants, assuming that there are about 175 species not in this group[3] and about 350,000 that are.[2] While such a clade with a similar circumscription exists in the APG III system, it was not given a name.[4]
Molecular clock comparisons of DNA sequences indicate that the mesangiosperms originated between 140 and 150 Mya (million years ago) near the beginning of the Cretaceous period.[10] This was about 25 Ma (million years) after the origin of the angiosperms in the mid-Jurassic.[11]
Because the interval of this radiation (about 4 million years) is short in proportion to its age (about 145 million years), it had long appeared that the 5 groups of mesangiosperms had arisen simultaneously. The mesangiosperms were shown as an unresolved pentatomyinphylogenetic trees. In 2007, two studies attempted to resolve the phylogeneticrelationships among these 5 groups by comparing large portions of their chloroplastgenomes.[11][12] These studies agreed on the most likely phylogeny for the mesangiosperms. In this phylogeny, the monocots are sister to the clade [Ceratophyllales + eudicots]. However, this result is not strongly supported. The approximately unbiased topology test showed that some of the other possible positions of the monocots had more than 5% probability of being correct. The major weakness of these 2 studies was the small number of species whose DNA was being used in the phylogenetic analysis, 45 in one study and 64 in the other.[11] This was unavoidable, because complete chloroplast genomesequences are known for only a few plants.
^ abAlan J. Paton, Neil Brummitt, Rafaël Govaerts, Kehan Harman, Sally Hinchcliffe, Bob Allkin, & Eimear Nic Lughadha (2008). "Towards Target 1 of the Global Strategy for Plant Conservation: a working list of all known plant species - progress and prospects". Taxon57(2):602-611.
^ abPeter F. Stevens (2001 onwards). Angiosperm Phylogeny Website In: Missouri Botanical Garden Website. (see External links below).
^Angiosperm Phylogeny Group (2009), "An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG III", Botanical Journal of the Linnean Society, 161 (2): 105–121, doi:10.1111/j.1095-8339.2009.00996.x, hdl:10654/18083
^Philip D. Cantino, James A. Doyle, Sean W. Graham, Walter S. Judd, Richard G. Olmstead, Douglas E. Soltis, Pamela S. Soltis, and Michael J. Donoghue. 2007. Electronic Supplement: pages E1-E44. To: Cantino et alii. 2007. "Towards a phylogenetic nomenclature of Tracheophyta". Taxon56(3):822-846. (see External links below).
^William E. Friedman and Kirsten C. Ryerson (2009). "Reconstructing the ancestral female gametophyte of angiosperms: Insights from Amborella and other ancient lineages of flowering plants". American Journal of Botany 96(1):129-143. doi:10.3732/ajb.0800311
^Else Marie Friis, K. Raunsgaard Pedersen, and Peter R. Crane (2006). "Cretaceous angiosperm flowers: Innovation and evolution in plant reproduction". Palaeogeography, Palaeoclimatology, Palaeoecology232(2-4):251-293. doi:10.1016/j.palaeo.2005.07.006
^T. Jonathan Davies, Timothy G. Barraclough, Mark W. Chase, Pamela S. Soltis, Douglas E. Soltis, and Vincent Savolainen (2004). "Darwin's abominable mystery: Insights from a supertree of the angiosperms". Proceedings of the National Academy of Sciences 101(7):1904-1909.
^ abcdMichael J. Moore, Charles D. Bell, Pamela S. Soltis, and Douglas E. Soltis (2007). "Using plastid genome-scale data to resolve enigmatic relationships among basal angiosperms". Proceedings of the National Academy of Sciences 104(49):19363-19368. doi:10.1073/pnas.0708072104
^Robert K. Jansen, Zhengqiu Cai, Linda A. Raubeson, Henry Daniell, Claude W. dePamphilis, James Leebens-Mack, Kai F. Müller, Mary Guisinger-Bellian, Rosemarie C. Haberle, Anne K. Hansen, Timothy W. Chumley, Seung-Bum Lee, Rhiannon Peery, Joel R. McNeal, Jennifer V. Kuehl, and Jeffrey L. Boore (2007). "Analysis of 81 genes from 64 plastid genomes resolves relationships in angiosperms and identifies genome-scale evolutionary patterns"
Proceedings of the National Academy of Sciences 104(49):19369-19374 doi:10.1073/pnas.0709121104