Project 802: S. Apesteguia, R. O. Gomez, G.W. Rougier. 2012. A basal sphenodontian (Lepidosauria) from the Jurassic of Patagonia: new insights on the phylogeny and biogeography of Gondwanan rhynocephalians. Zoological Journal of the Linnean Society. 166 (2):342-360.
Specimen: † Sphenocondor gracilis (MPEF/PV:2358)

Abstract

Herein we describe a new rhynchocephalian taxon from the Middle Jurassic of Patagonia, Argentina, representing the first Jurassic record of the group in South America. The new taxon, consisting of a complete dentary, is ascribed to Sphenodontia based on the presence of a deep and wide Meckelian groove, long posterior process, well-developed coronoid process, and acrodont teeth showing dental regionalization including successional, alternate hatchling, and additional series. This allocation is reinforced by a phylogenetic analysis that places the new taxon in a basal position within a clade of sphenodontians that excludes Diphydontosaurus and Planocephalosaurus. Additionally, the new taxon clusters within a Gondwanan clade with the Indian Godavarisaurus from the Jurassic Kota Formation, sharing the presence of recurved and relatively large posterior successional teeth that are ribbed and bear a peculiar anterolingual groove. This sister-group relationship is intriguing from a palaeobiogeographical viewpoint, as it suggests some degree of endemism during the initial stages of the breakup of Pangaea. We also discuss the ontogenetic stage of the new taxon and provide insights on the evolution of successional dentition in rhynchocephalians.


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Project DOI: 10.7934/P802, http://dx.doi.org/10.7934/P802
This project containsMatrices
  • 1 Media
  • 1 Matrix
  • 1 Document
  • 27 Taxa
  • 1 Specimen
  • 73 Characters
Total size of project's media files: 2 MB

Download Project SDD File
Total scored cells: 1147
Total media associated with cells: 0
Total labels associated with cell media: 0
Characters
Total characters: 73
Total characters with associated media: 0
Total characters with media with labels: 0
Total character states: 173
Total character states with associated media: 0
Total character states with media with labels:0
Total unordered/ordered characters:0/73
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MorphoBank Project 802


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    Maureen Admin
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    Sebastian Apesteguia
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    Taxonomic Overview for Matrix 'M1829' (26 Taxa)

    taxon unscored
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    cells
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    [1] † Youngina
    Last Modified in 12/05/13
    8656500003
    [2] † Pristidactylus
    Last Modified in 12/05/13
    17565600003
    [3] † Gephyrosaurus
    Last Modified in 12/05/13
    10636300003
    [4] † Diphydontosaurus
    Last Modified in 12/05/13
    2717100003
    [5] † Planocephalosaurus
    Last Modified in 12/05/13
    4716900003
    [6] † Rebbanasaurus
    Last Modified in 12/05/13
    43313000003
    [7] † Godavarisaurus
    Last Modified in 12/05/13
    46302700003
    [8] † Homoeosaurus
    Last Modified in 12/05/13
    18585500003
    [9] † Palaeopleurosaurus
    Last Modified in 12/05/13
    9646400003
    [10] † Brachyrhinodon
    Last Modified in 12/05/13
    22515100003
    [11] † Clevosaurus hudsoni
    Last Modified in 12/05/13
    3707000003
    [12] † Kallimodon
    Last Modified in 12/05/13
    13606000003
    [13] † Sapheosaurus
    Last Modified in 12/05/13
    34393900003
    [14] † Pamizinsaurus
    Last Modified in 12/05/13
    44312900003
    [15] † Zapatadon
    Last Modified in 12/05/13
    37373600003
    [16] † Sphenodon
    Last Modified in 12/05/13
    0757300003
    [17] † Cynosphenodon
    Last Modified in 12/05/13
    48252500003
    [18] † Opisthias
    Last Modified in 12/05/13
    26474700003
    [19] † Toxolophosaurus
    Last Modified in 12/05/13
    54191900003
    [20] † Eilenodon
    Last Modified in 12/05/13
    44292900003
    [21] † Kaikaifilusaurus avelasi
    Last Modified in 12/05/13
    8656500003
    [22] † Ankylosphenodon
    Last Modified in 12/05/13
    49242400003
    [23] † Sphenocondor
    Last Modified in 12/05/13
    54211900003
    [24] † Sphenovipera
    Last Modified in 12/05/13
    54201900003
    [25] † Theretairus
    Last Modified in 12/05/13
    58151500003
    [26] † Kawasphenodon
    Last Modified in 12/05/13
    63101000003


    Project views

    type number of views Individual items viewed (where applicable)
    Total project views25075
    Project overview2808
    Documents list1551
    Matrix views2214Matrix landing page (1923 views); Sphenocondor matrix (291 views);
    Media views4240Media search (3751 views); M149580 (489 views);
    Specimen list1917
    Taxon list11516
    Bibliography829




    Project downloads

    type number of downloads Individual items downloaded (where applicable)
    Total downloads from project230
    Document downloads2Copyright Permission (2 downloads);
    Matrix downloads14Sphenocondor matrix (14 downloads);
    Project downloads212
    Media downloads2M149580 (2 downloads);