Project 2788: N. G. Zverkov, V. M. Efimov. 2019. Revision of Undorosaurus, a mysterious Late Jurassic ichthyosaur of the Boreal Realm. Journal of Systematic Palaeontology. 17 (14):1183-1213.
Specimen: † Undorosaurus gorodischensis Efimov, 1999 (PMO/214.578:214.578)
View: skeleton and its reconstruction in left lateral view

Abstract

Recent study of ophthalmosaurid ichthyosaurs has brought us a number of new taxa; however, the validity of several ophthalmosaurid taxa from the Volgian (Tithonian) of European Russia still remains unclear, complicating comparisons and in some cases affecting taxonomic decisions about new contributions. A revision of the type series of all three species of Undorosaurus, erected by Efimov in 1999, reveals the potential validity of two of them. This contradicts previous research, which concluded that only the type species, U. gorodischensis, is valid. Furthermore, examination of the holotype of Cryopterygius kristiansenae from coeval strata of Svalbard shows that it is synonymous with Undorosaurus gorodischensis, sharing all diagnostic features of the species, especially those related to forelimb morphology: humerus with extensive anteroposteriorly elongate proximal end, poorly pronounced trochanter dorsalis and reduced deltopectoral crest; and ulna proximodistally elongate and not involved in perichondral ossification on its whole posterior edge. This supports the idea of intensive exchange of ichthyosaurs between the Middle Russian Sea and other Boreal seas in the Late Jurassic. In order to resolve the phylogenetic position of Undorosaurus within Ophthalmosauridae as well as relationships of other ophthalmosaurids, a new data set including 33 taxa and 106 characters, 23 of which are new, was compiled. The results of this analysis challenge all previous phylogenetic hypotheses for Ophthalmosauridae in a number of aspects, including the fact that Undorosaurus spp. was recovered deeply nested within Platypterygiinae as a sister group to derived platypterygiines.


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Article DOI: 10.1080/14772019.2018.1515793

Project DOI: 10.7934/P2788, http://dx.doi.org/10.7934/P2788
This project containsMatrices
  • 1 Media
  • 2 Matrices
  • 36 Taxa
  • 1 Specimen
  • 106 Characters
Total size of project's media files: 1.11M

Download Project SDD File
Total scored cells: 4299
Total media associated with cells: 0
Total labels associated with cell media: 0
Characters
Total characters: 212
Total characters with associated media: 0
Total characters with media with labels: 0
Total character states: 227
Total character states with associated media: 0
Total character states with media with labels:0
Total unordered/ordered characters:208/4
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MorphoBank Project 2788

    Authors' Institutions

    • Lomonosov Moscow State University

    • Russian Academy of Sciences

    • Undory Paleontological Museum



    Members

    member name taxa specimens media chars character
    media
    labels
    cell scorings
    (scored, NPA, "-")
    cell
    medialabels
    rules
    Nikolay Zverkov
    Project Administrator
    3611212004299
    (4299, 0, 0)
    000


    Taxonomic Overview for Matrix 'M25432' (33 Taxa)

    taxon unscored
    cells
    scored
    cells
    no cell
    support
    NPA
    cells
    "-" cellscell images labels on
    cell images
    member
    access
    [1] † Temnodontosaurus spp.
    Last Modified in 01/24/19
    510110100001
    [2] † Ichthyosaurus communis
    Last Modified in 01/24/19
    110910500001
    [3] † Hauffiopteryx typicus
    Last Modified in 01/24/19
    29777700001
    [4] † Stenopterygius quadriscissus
    Last Modified in 01/24/19
    110810500001
    [5] † Chacaicosaurus cayi
    Last Modified in 01/24/19
    77292900001
    [6] † Stenopterygius aaleniensis
    Last Modified in 01/24/19
    47595900001
    [7] † Ophthalmosaurus icenicus
    Last Modified in 01/24/19
    010810600001
    [8] † Ophthalmosaurus natans
    Last Modified in 01/24/19
    29777700001
    [9] † Mollesaurus periallus
    Last Modified in 01/24/19
    74333200001
    [10] † Acamptonectes densus
    Last Modified in 01/24/19
    48605800001
    [11] † Leninia stellans
    Last Modified in 01/24/19
    72343400001
    [12] † Arthropterygius chrisorum
    Last Modified in 01/24/19
    65414100001
    [13] † Janusaurus lundi
    Last Modified in 01/24/19
    34737200001
    [14] † Palvennia hoybergeti
    Last Modified in 01/24/19
    34727200001
    [15] † Keilhauia nui
    Last Modified in 01/24/19
    75313100001
    [16] † Grendelius alekseevi
    Last Modified in 01/24/19
    38686800001
    [17] † Grendelius mordax
    Last Modified in 01/24/19
    40676600001
    [18] † Caypullisaurus bonapartei
    Last Modified in 01/24/19
    48605800001
    [19] † Aegirosaurus leptospondylus
    Last Modified in 01/24/19
    48595800001
    [20] † Undorosaurus gorodischensis
    Last Modified in 05/11/18
    10999600001
    [21] † Undorosaurus nessovi
    Last Modified in 05/13/18
    60464600001
    [22] † Nannopterygius enthekiodon
    Last Modified in 01/24/19
    79272700001
    [23] † Parophthalmosaurus saveljeviensis
    Last Modified in 01/24/19
    11979500001
    [24] † Gengasaurus nicosiai
    Last Modified in 01/24/19
    73333300001
    [25] † Athabascasaurus bitumineus
    Last Modified in 01/24/19
    59474700001
    [26] † Sveltonectes insolitus
    Last Modified in 01/24/19
    27807900001
    [27] † Plutoniosaurus bedengensis
    Last Modified in 01/24/19
    36707000001
    [28] † Maiaspondylus lindoei
    Last Modified in 01/24/19
    72343400001
    [29] † Platypterygius australis
    Last Modified in 01/24/19
    410310200001
    [30] † Platypterygius hercynicus
    Last Modified in 01/24/19
    33747300001
    [31] † Platypterygius americanus
    Last Modified in 01/24/19
    50565600001
    [32] † Platypterygius platydactylus
    Last Modified in 01/24/19
    60474600001
    [33] † Sisteronia seeleyi
    Last Modified in 01/24/19
    75323100001


    Taxonomic Overview for Matrix 'M25433' (34 Taxa)

    taxon unscored
    cells
    scored
    cells
    no cell
    support
    NPA
    cells
    "-" cellscell images labels on
    cell images
    member
    access
    [1] † Temnodontosaurus spp.
    Last Modified in 01/24/19
    510110100001
    [2] † Ichthyosaurus communis
    Last Modified in 01/24/19
    110910500001
    [3] † Hauffiopteryx typicus
    Last Modified in 01/24/19
    29777700001
    [4] † Stenopterygius quadriscissus
    Last Modified in 01/24/19
    110810500001
    [5] † Chacaicosaurus cayi
    Last Modified in 01/24/19
    77292900001
    [6] † Stenopterygius aaleniensis
    Last Modified in 01/24/19
    47595900001
    [7] † Ophthalmosaurus icenicus
    Last Modified in 01/24/19
    010810600001
    [8] † Ophthalmosaurus natans
    Last Modified in 01/24/19
    29777700001
    [9] † Mollesaurus periallus
    Last Modified in 01/24/19
    74333200001
    [10] † Acamptonectes densus
    Last Modified in 01/24/19
    48605800001
    [11] † Leninia stellans
    Last Modified in 01/24/19
    72343400001
    [12] † Arthropterygius chrisorum
    Last Modified in 01/24/19
    65414100001
    [13] † Janusaurus lundi
    Last Modified in 01/24/19
    34737200001
    [14] † Palvennia hoybergeti
    Last Modified in 01/24/19
    34727200001
    [15] † Keilhauia nui
    Last Modified in 01/24/19
    75313100001
    [16] † Grendelius alekseevi
    Last Modified in 01/24/19
    38686800001
    [17] † Grendelius mordax
    Last Modified in 01/24/19
    40676600001
    [18] † Caypullisaurus bonapartei
    Last Modified in 01/24/19
    48605800001
    [19] † Aegirosaurus leptospondylus
    Last Modified in 01/24/19
    48595800001
    [20] † Undorosaurus gorodischensis upm
    Last Modified in 01/24/19
    25848100001
    [21] † Undorosaurus gorodischensis pmo
    Last Modified in 01/24/19
    17928900001
    [22] † Undorosaurus nessovi
    Last Modified in 05/13/18
    60464600001
    [23] † Nannopterygius enthekiodon
    Last Modified in 01/24/19
    79272700001
    [24] † Parophth saveljeviensis
    Last Modified in 01/24/19
    11979500001
    [25] † Gengasaurus nicosiai
    Last Modified in 01/24/19
    73333300001
    [26] † Athabascasaurus bitumineus
    Last Modified in 01/24/19
    59474700001
    [27] † Sveltonectes insolitus
    Last Modified in 01/24/19
    27807900001
    [28] † Plutoniosaurus bedengensis
    Last Modified in 01/24/19
    36707000001
    [29] † Maiaspondylus lindoei
    Last Modified in 01/24/19
    72343400001
    [30] † Platypterygius australis
    Last Modified in 01/24/19
    410310200001
    [31] † Platypterygius hercynicus
    Last Modified in 01/24/19
    33747300001
    [32] † Platypterygius americanus
    Last Modified in 01/24/19
    50565600001
    [33] † Platypterygius platydactylus
    Last Modified in 01/24/19
    60474600001
    [34] † Sisteronia seeleyi
    Last Modified in 01/24/19
    75323100001


    Project views

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    Total project views16381
    Project overview1807
    Matrix views1104Matrix landing page (864 views); Matrix_Zverkov&Efimov_Undorosaurus_revision (134 views); Matrix2_Zverkov&Efimov_Undorosaurus_revision_PMO (106 views);
    Media views3111Media search (2395 views); M466062 (716 views);
    Views for media list868
    Specimen list1465
    Taxon list7408
    Bibliography613
    Documents list5




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    type number of downloads Individual items downloaded (where applicable)
    Total downloads from project165
    Project downloads144
    Matrix downloads15Matrix_Zverkov&Efimov_Undorosaurus_revision (8 downloads); Matrix2_Zverkov&Efimov_Undorosaurus_revision_PMO (7 downloads);
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