Life » » Plants »


Brief Summary

Comprehensive Description

    provided by wikipedia

    The Saxifragales are an order of flowering plants.[1] Their closest relatives are a large eudicot group known as the rosids by the definition of rosids given in the APG II classification system.[2] Some authors define the rosids more widely, including Saxifragales as their most basal group.[3] Saxifragales is one of the eight groups that compose the core eudicots. The others are Gunnerales, Dilleniaceae, Rosids, Santalales, Berberidopsidales, Caryophyllales, and Asterids.[4]

    Saxifragales have an extensive fossil record.[5][6][7][8][9][10] The extant members are apparently remnants of a formerly diverse and widespread order.[11]

    The Saxifragales order, as it is now understood, is based upon the results of molecular phylogenetic studies of DNA sequences. It is not part of any of the classification systems based on plant morphology. The group is much in need of comparative anatomical study, especially in light of the recent expansion of the family Peridiscaceae to include Medusandra, a genus that before 2009 had usually not been placed in Saxifragales.[12]

    The order is divided into suprafamilial groups as shown on the phylogenetic tree below. These groups are informal and are not understood to have any particular taxonomic rank.


    Saxifragales contain about 2470 species.[13] These are distributed into 15 families,[11] or into 12 families if Haloragaceae sensu lato is recognized as a family consisting of Haloragaceae sensu stricto, Penthorum, Tetracarpaea, and Aphanopetalum.[13] About 95% of the species are in five families: Crassulaceae (1400), Saxifragaceae (500), Grossulariaceae (150 - 200), Haloragaceae (150), and Hamamelidaceae (100). Most of the families are monogeneric. The number of genera in each family is:

    Some authors do not recognize Choristylis as a separate genus from Itea.[15] Similarly, some authors sink Liquidambar and Semiliquidambar into Altingia.[16] Thus Altingiaceae and Iteaceae are monogeneric in some classifications.


    Within the Saxifragales is a suprafamilial group known as the Saxifragaceae alliance. It comprises four families: Pterostemonaceae, Iteaceae, Grossulariaceae, and Saxifragaceae.[13] These have long been known to be related to each other, but the circumscription of Saxifragaceae has changed dramatically. It is now a much smaller family than it had been.[17] Crassulaceae [18] and Tetracarpaeaceae [19] have long been associated with Saxifragaceae. Penthorum has usually been associated with Crassulaceae, but sometimes with Saxifragaceae.[20]

    Two members of the core Saxifragales had sometimes been placed near Saxifragaceae, but usually elsewhere. Aphanopetalum was often placed in Cunoniaceae, a family in Oxalidales, even though there were good reasons to put it in Saxifragales.[21] Aphanopetalum is now excluded from Cunoniaceae.[22] Haloragaceae was often thought to be a family in Myrtales,[23] but it is no longer included in that order.[24]

    Cercidiphyllaceae had for a long time been associated with Hamamelidaceae and Trochodendraceae and was often thought to be closer to the latter.[25] Cercidiphyllaceae is now known to be a member of the woody clade of Saxifragales, along with Hamamelidaceae, Altingiaceae, and Daphniphyllaceae, but Trochodendraceae is in the basal eudicot order Trochodendrales.[26] Altingiaceae was usually not separated from Hamamelidaceae until phylogenetic studies showed that its inclusion might make Hamamelidaceae paraphyletic. The recognition of Altingiaceae as a separate family received strong statistical support in 2008.[13]

    Daphniphyllum was always thought to have an anomalous combination of characters [27][28] and it was placed in several different orders before molecular phylogenetic analysis showed it to belong to Saxifragales.[29]

    Paeoniaceae possesses many unique features and its taxonomic position was for a long time controversial.[30] The idea has long persisted that Paeonia belongs in Ranunculales, close to Glaucidium.[31][32] Paeoniaceae has been shown unequivocally to belong in Saxifragales,[13] while Glaucidium is in the family Ranunculaceae.[33]

    The family Peridiscaceae underwent radical shifting and recircumscription from 2003 to 2009. Originally, it consisted of two closely related genera, Peridiscus and Whittonia. The APG II system placed the family in Malpighiales, based on a DNA sequence for the rbcL gene from Whittonia. This sequence turned out to be not from Whittonia, but from other plants whose DNA had contaminated the sample.[34] After Peridiscaceae was finally placed in Saxifragales, it was expanded to include Soyauxia in 2007,[35] and expanded again to include Medusandra in 2009.[12]


    The phylogeny shown below is based on the one published by Shuguang Jian and coauthors in 2008.[13] All branches have 100% maximum likelihood bootstrap support except where labeled with bootstrap percentage. Monogeneric families are represented by genus names.

    .mw-parser-output table.clade{border-spacing:0;margin:0;font-size:100%;line-height:100%;border-collapse:separate;width:auto}.mw-parser-output table.clade table.clade{width:100%}.mw-parser-output table.clade td{border:0;padding:0;vertical-align:middle;text-align:center}.mw-parser-output table.clade td.clade-label{width:0.8em;border:0;padding:0 0.2em;vertical-align:bottom;text-align:center}.mw-parser-output table.clade td.clade-slabel{border:0;padding:0 0.2em;vertical-align:top;text-align:center}.mw-parser-output table.clade td.clade-bar{vertical-align:middle;text-align:left;padding:0 0.5em}.mw-parser-output table.clade td.clade-leaf{border:0;padding:0;text-align:left;vertical-align:middle}.mw-parser-output table.clade td.clade-leafR{border:0;padding:0;text-align:right} Saxifragales


      97 woody clade  




      69 98






              core Saxifragales    


      Haloragaceae sensu lato  








              Saxifragaceae alliance    










    1. ^ Soltis, Douglas E.; Soltis, Pamela S.; Endress, Peter K.; Chase, Mark W. (2005). Phylogeny and Evolution of the Angiosperms. Sunderland, MA, USA: Sinauer. ISBN 978-0-87893-817-9.mw-parser-output cite.citation{font-style:inherit}.mw-parser-output q{quotes:"""""'"'"}.mw-parser-output code.cs1-code{color:inherit;background:inherit;border:inherit;padding:inherit}.mw-parser-output .cs1-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/thumb/6/65/Lock-green.svg/9px-Lock-green.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-limited a,.mw-parser-output .cs1-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/thumb/d/d6/Lock-gray-alt-2.svg/9px-Lock-gray-alt-2.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/thumb/a/aa/Lock-red-alt-2.svg/9px-Lock-red-alt-2.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration{color:#555}.mw-parser-output .cs1-subscription span,.mw-parser-output .cs1-registration span{border-bottom:1px dotted;cursor:help}.mw-parser-output .cs1-hidden-error{display:none;font-size:100%}.mw-parser-output .cs1-visible-error{font-size:100%}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration,.mw-parser-output .cs1-format{font-size:95%}.mw-parser-output .cs1-kern-left,.mw-parser-output .cs1-kern-wl-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right,.mw-parser-output .cs1-kern-wl-right{padding-right:0.2em}
    2. ^ Hengchang Wang, Michael J. Moore, Pamela S. Soltis, Charles D. Bell, Samuel F. Brockington, Roolse Alexandre, Charles C. Davis, Maribeth Latvis, Steven R. Manchester, and Douglas E. Soltis (10 Mar 2009). "Rosid radiation and the rapid rise of angiosperm-dominated forests". Proceedings of the National Academy of Sciences. 106 (10): 3853–3858. doi:10.1073/pnas.0813376106. PMC 2644257. PMID 19223592CS1 maint: Multiple names: authors list (link)
    3. ^ J. Gordon Burleigh; Khidir W. Hilu & Douglas E. Soltis (2009). "Inferring phylogenies with incomplete data sets: a 5-gene, 567-taxon analysis of angiosperms". BMC Evolutionary Biology. 9 (1): 61. doi:10.1186/1471-2148-9-61. PMC 2674047. PMID 19292928 |contribution= ignored (help)
    4. ^ Peter F. Stevens. 2001 onwards. "Trees". At: Angiosperm Phylogeny Website At: Missouri Botanical Garden Website. (see External links below).
    5. ^ Elizabeth J. Hermsen, María A. Gandolfo, Kevin C. Nixon, and William L. Crepet. 2006. "The impact of extinct taxa on understanding the early evolution of angiosperm clades: An example incorporating fossil reproductive structures of Saxifragales". Plant Systematics and Evolution 260:141–169.
    6. ^ Hermsen, Elizabeth J.; Gandolfo, María A.; Nixon, Kevin C.; Crepet, William L. (2003). "Divisestylus genus novus (Affinity Iteaceae), a fossil saxifrage from the Late Cretaceous of New Jersey, USA". American Journal of Botany. 90 (9): 1373–1388. doi:10.3732/ajb.90.9.1373. PMID 21659237.
    7. ^ Pigg, Kathleen B.; Ickert-Bond, Stephanie M.; Wen, Jun (2004). "Anatomically preserved Liquidambar (Altingiaceae) from the middle Miocene of Yakima Canyon, Washington State, USA, and its biogeographic implications". American Journal of Botany. 91 (3): 499–509. doi:10.3732/ajb.91.3.499. PMID 21653405.
    8. ^ Hernández-Castillo, Genaro R.; Cevallos-Ferriz, Sergio R.S. (1999). "Reproductive and vegetative organs with affinities to Haloragaceae from the Upper Cretaceous Huepac Chert Locality of Sonora, Mexico". American Journal of Botany. 86 (12): 1717–1734. doi:10.2307/2656670. JSTOR 2656670. PMID 10602765.
    9. ^ Crane, Peter R. (1989). "Paleobotanical evidence on the early radiation of nonmagnoliid dicotyledons". Plant Systematics and Evolution. 162: 165–191. doi:10.1007/BF00936916.
    10. ^ Endress, Peter K. (1989). "Aspects of evolutionary differentiation of the Hamamelidaceae and the Lower Hamamelididae". Plant Systematics and Evolution. 162: 193–211. doi:10.1007/BF00936917.
    11. ^ a b Klaus Kubitzki. 2007. "Introduction to Saxifragales". pages 15-18. In: Klaus Kubitski (editor). The Families and Genera of Vascular Plants volume IX. Springer-Verlag: Berlin;Heidelberg, Germany.
    12. ^ a b Kenneth J. Wurdack and Charles C. Davis. 2009. "Malpighiales phylogenetics: Gaining ground on one of the most recalcitrant clades in the angiosperm tree of life." American Journal of Botany 96(8):1551-1570. (see External links below)
    13. ^ a b c d e f Shuguang Jian, Pamela S. Soltis, Matthew A. Gitzendanner, Michael J. Moore, Ruiqi Li, Tory A. Hendry, Yin-Long Qiu, Amit Dhingra, Charles D. Bell, and Douglas E. Soltis. 2008. "Resolving an Ancient, Rapid Radiation in Saxifragales". Systematic Biology 57(1):38-57. (see External links below).
    14. ^ Peter F. Stevens. 2001 onwards. "Saxifragales" At: Angiosperm Phylogeny Website At: Missouri Botanical Garden Website. (see External links below).
    15. ^ Klaus Kubitzki. 2007. "Iteaceae". pages 202-204. In: Klaus Kubitski (editor). The Families and Genera of Vascular Plants volume IX. Springer-Verlag: Berlin;Heidelberg, Germany.
    16. ^ Ickert-Bond, Stephanie M.; Wen, Jun (2006). "Phylogeny and biogeography of Altingiaceae: Evidence from combined analysis of five non-coding chloroplast regions". Molecular Phylogenetics and Evolution. 39 (2): 512–528. doi:10.1016/j.ympev.2005.12.003. PMID 16439163.
    17. ^ Soltis, Douglas E.; Kuzoff, Robert K.; Mort, Mark E.; Zanis, Michael; Fishbein, Mark; Hufford, Larry; Koontz, Jason; Arroyo, Mary K. (2001). "Elucidating deep-level phylogenetic relationships in Saxifragaceae using sequences for six chloroplastic and nuclear DNA regions". Annals of the Missouri Botanical Garden. 88 (4): 669–693. doi:10.2307/3298639. JSTOR 3298639.
    18. ^ Joachim Thiede and Urs Eggli. 2007. "Crassulaceae". pages 83-118. In: Klaus Kubitski (editor). The Families and Genera of Vascular Plants volume IX. Springer-Verlag: Berlin;Heidelberg, Germany.
    19. ^ Hils, Matthew H.; Dickison, William C.; Lucansky, Terry W.; William Louis, Stern (1988). "Comparative anatomy and systematics of woody Saxifragaceae: Tetracarpaea". American Journal of Botany. 75 (11): 1687–1700. doi:10.2307/2444685. JSTOR 2444685.
    20. ^ Joachim Thiede. 2007. "Penthoraceae". pages 292-296. In: Klaus Kubitski (editor). The Families and Genera of Vascular Plants volume IX. Springer-Verlag: Berlin;Heidelberg, Germany.
    21. ^ Dickison, William C.; Hils, Matthew H.; Lucansky, Terry W.; William Louis, Stern (1994). "Comparative anatomy and systematics of woody Saxifragaceae: Aphanopetalum". Botanical Journal of the Linnean Society. 114 (2): 167–182. doi:10.1111/j.1095-8339.1994.tb01930.x.
    22. ^ Jason C. Bradford, Helen C. Fortune-Hopkins, and Richard W. Barnes. 2004. "Cunoniaceae". pages 91-111. In: Klaus Kubitski (editor). The Families and Genera of Vascular Plants volume VI. Springer-Verlag: Berlin;Heidelberg, Germany.
    23. ^ Klaus Kubitzki. 2007. "Haloragaceae". pages 184-190. In: Klaus Kubitski (editor). The Families and Genera of Vascular Plants volume IX. Springer-Verlag: Berlin;Heidelberg, Germany.
    24. ^ Moody, Michael L.; Les, Donald H. (2007). "Phylogenetic systematics and character evolution in the angiosperm family Haloragaceae". American Journal of Botany. 94 (12): 2005–2025. doi:10.3732/ajb.94.12.2005. PMID 21636395.
    25. ^ Endress, Peter K. (1986). "Floral structure, systematics and phylogeny in Trochodendrales". Annals of the Missouri Botanical Garden. 73 (2): 297–324. doi:10.2307/2399115. JSTOR 2399115.
    26. ^ Worberg, Andreas; Quandt, Dietmar; Anna-, Anna-Magdalena; Barniske, Magdalena; Löhne, Cornelia; Hilu, Khidir W.; Borsch, Thomas (2007). "Phylogeny of basal eudicots: Insights from non-coding and rapidly evolving DNA". Organisms Diversity and Evolution. 7 (1): 55–77. doi:10.1016/j.ode.2006.08.001.
    27. ^ Tseng-Chieng, Huang (1965). "Monograph of Daphniphyllum (I)". Taiwania. 11: 57–98.
    28. ^ Tseng-Chieng, Huang (1966). "Monograph of Daphniphyllum (II)". Taiwania. 12: 137–234.
    29. ^ Klaus Kubitzki. 2007. "Daphniphyllaceae". pages 127-128. In: Klaus Kubitski (editor). The Families and Genera of Vascular Plants volume IX. Springer-Verlag: Berlin;Heidelberg, Germany.
    30. ^ Michio Tamura. 2007. "Paeoniaceae". pages 265-269. In: Klaus Kubitski (editor). The Families and Genera of Vascular Plants volume IX. Springer-Verlag: Berlin;Heidelberg, Germany.
    31. ^ David J. Mabberley. 2008. Mabberley's Plant-Book third edition (2008). Cambridge University Press: UK.
    32. ^ Josef J. Halda and James W. Waddick. 2004. The genus Paeonia. Timber Press: Oregon, USA.
    33. ^ Wei Wang; An-Ming Lu; Yi Ren; Mary E. Endress; Zhi-Duan Chen (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. doi:10.1016/j.ppees.2009.01.001.
    34. ^ Davis, Charles C.; Chase, Mark W. (2004). "Elatinaceae are sister to Malpighiaceae; Peridiscaceae belong to Saxifragales". American Journal of Botany. 91 (2): 262–273. doi:10.3732/ajb.91.2.262. PMID 21653382.
    35. ^ Soltis, Douglas E.; Clayton, Joshua W.; Davis, Charles C.; Gitzendanner, Matthew A.; Cheek, Martin; Savolainen, Vincent; Amorim, André M.; Soltis, Pamela S. (2007). "Monophyly and relationships of the enigmatic family Peridiscaceae". Taxon. 56 (1): 65–73.