Project 295: J. Liu, P. Olsen. 2010. The phylogenetic relationships of Eucynodontia (Amniota: Synapsida). Journal of Mammalian Evolution. 17 (3):151-176.
Specimen: † Bienotherium yunnanense (IVPP/V:1)
View: ventral

Abstract

The phylogenetic interrelationships of Eucynodontia are very important topic in vertebrate paleontology and are the foundation to understand the origin of mammalian. However, the consensus on the phylogenetic interrelationships of Eucynodontia remains elusive. To clarify these phylogenetic interrelationships of Eucynodontia, a cladistics analysis, based on 145 characters and 31 species and integrated all prior works, was performed. The monophyly of Eucynodontia is confirmed, although the results differ slightly from those of previous analyses with respect to the composition of both Cynognathia and Probainognathia. This is also the first numerical cladistic analysis to recover a monophyletic Traversodontidae. Tritheledonta cannot be monophyletic in any case, and this name is not recommended for formal taxonomic use. Brasilodon is the plesiomorphic sister taxon of mMammalias, although it is younger than the oldest mammals and is specialized in some characters. A monophyletic Mammaliamorpha, including all trithelodontans, tritylodontids and mammals, is well supported by many characters.
Pruning highly incomplete taxa has little effect on the inferred pattern of relationships among the more complete taxa, although this pattern can change according to the inclusion or exclusion of basal fragmentary taxa. Different taxa Taxon sampling onf the current data matrix shows that taxon sampling was poor in some previous studies, implying that their results are not reliable. Two major unresolved questions in cynodont phylogenetics are whether tritylodontids are more closely related to mammals or to traversodontids, and whether tritylodontids or trithelodontids are closer to mammals. We compare previously topologies and our topology for congruence with the stratigraphic record. Analysis Analyses of possible synapomorphies and stratigraphic data supports a relatively close relationship between mammals and tritylodontids, to the exclusion of traversodontids, but does not clearly indicate whether or not trithelodontids are even more closer to mammals than are tritylodontids.


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Article DOI: 10.1007/s10914-010-9136-8

Project DOI: 10.7934/P295, http://dx.doi.org/10.7934/P295
This project containsMatrices
  • 1 Media
  • 1 Matrix
  • 1 Document
  • 34 Taxa
  • 1 Specimen
  • 145 Characters
Total size of project's media files: 1.24M

Download Project SDD File
Total scored cells: 3616
Total media associated with cells: 0
Total labels associated with cell media: 0
Characters
Total characters: 145
Total characters with associated media: 0
Total characters with media with labels: 0
Total character states: 355
Total character states with associated media: 0
Total character states with media with labels:0
Total unordered/ordered characters:145/0
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MorphoBank Project 295

    Authors' Institutions

    • Chinese Academy of Sciences

    • Columbia University

    • Institute of Vertebrate Paleontology and Paleoanthropology (IVPP), CAS



    Members

    member name taxa specimens media chars character
    media
    labels
    cell scorings
    (scored, NPA, "-")
    cell
    medialabels
    rules
    Jun Liu
    Project Administrator
    3301145003616
    (3524, 0, 92)
    000


    Taxonomic Overview for Matrix 'M733' (31 Taxa)

    taxon unscored
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    "-" cellscell images labels on
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    [1] Procynosuchus
    Last Modified in 12/05/13
    014114005001
    [2] Galesaurus
    Last Modified in 12/05/13
    813413403001
    [3] Thrinaxodon
    Last Modified in 12/05/13
    114013905001
    [4] Platycraniellus
    Last Modified in 12/05/13
    3910310303001
    [5] Cynognathus
    Last Modified in 12/05/13
    114114103001
    [6] Diademodon
    Last Modified in 12/05/13
    114614400001
    [7] Trirachodon
    Last Modified in 12/05/13
    713913800001
    [8] Sinognathus
    Last Modified in 12/05/13
    48979700001
    [9] Langbergia
    Last Modified in 12/05/13
    3610910900001
    [10] Pascualgnathus
    Last Modified in 12/05/13
    3411210902001
    [11] Luangwa
    Last Modified in 12/05/13
    3710810602001
    [12] Massetognathus
    Last Modified in 12/05/13
    414013902001
    [13] Exaeretodon
    Last Modified in 12/05/13
    813813502001
    [14] Scalenodon
    Last Modified in 12/05/13
    57898602001
    [15] "Scalenodon"
    Last Modified in 12/05/13
    76706702001
    [16] Chiniquodon
    Last Modified in 12/05/13
    813513403001
    [17] Lumkuia
    Last Modified in 12/05/13
    2711511503001
    [18] Ectenion
    Last Modified in 12/05/13
    2611811603001
    [19] Probainognathus
    Last Modified in 12/05/13
    713513503001
    [20] Prozostrodon
    Last Modified in 12/05/13
    76666603001
    [21] Therioherpeton
    Last Modified in 12/05/13
    96464603001
    [22] Riograndia
    Last Modified in 12/05/13
    4110210103001
    [23] Pachygenelus
    Last Modified in 12/05/13
    713513503001
    [24] Brasilodon
    Last Modified in 12/05/13
    3211111003001
    [25] Oligokyphus
    Last Modified in 12/05/13
    2611311207001
    [26] Tritylodon
    Last Modified in 12/05/13
    1911911907001
    [27] Kayentatherium
    Last Modified in 12/05/13
    713113107001
    [28] Bienotherium
    Last Modified in 12/05/13
    2511311307001
    [29] Adelobasileus
    Last Modified in 12/05/13
    105404000001
    [30] Sinoconodon
    Last Modified in 12/05/13
    4110110103001
    [31] Morganucodon
    Last Modified in 12/05/13
    513713703001


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    Total project views34640
    Project overview2967
    Media views5882Media search (4890 views); M402394 (990 views); M402395 (2 views);
    Matrix views2342Matrix landing page (2049 views); Data matrix for iphylogenetic relationships of Eucynodontia (293 views);
    Views for media list1535
    Taxon list16699
    Bibliography1041
    Documents list1643
    Specimen list2531




    Project downloads

    type number of downloads Individual items downloaded (where applicable)
    Total downloads from project293
    Project downloads280
    Matrix downloads6Data matrix for iphylogenetic relationships of Eucynodontia (6 downloads);
    Document downloads6character list and codings (6 downloads);
    Media downloads1M402394 (1 download);