Project 4059: A. G. Martinelli, F. Agnolin, M. Ezcurra. 2021. Unexpected new lizard from the Late Cretaceous of southern South America sheds light on Gondwanan squamate diversity. Revista del Museo Argentino de Ciencias Naturales. 23:57-80.
Specimen: † Paleochelco occultato Martinelli, Agnolín & Ezcurra, 2021 (MACN/MACN-Pv-N:120)
View: Left view of partial skull


The record of Cretaceous terrestrial lizard (Squamata) in South America is patchy, with seven species described from north-eastern and south-eastern Brazil, and few isolated records of iguanians and scincomorphans from Patagonia Argentina. Herein we describe a new genus and species of cretaceous lizard, Paleochelco occultato gen. et sp. nov., based on partial skull (MACN-Pv-N 120) discovered about three decades ago that was unnoticed in the Colección Paleovertebrados of the Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”. It comes from rocks of the Upper Cretaceous Bajo de la Carpa Formation (Neuquén Group) exposed at the Campus of the Universidad Nacional del Comahue, north of Neuquén City (Neuquén Province). The new taxon was included into a broad phylogenetic dataset of squamates and it was recovered around the base of Polyglyphanodontia in a constrained analysis using a molecular backbone. By contrast, the same, but topologically unconstrained analysis found Paleochelco occultato also around the base of Polyglyphanodontia but alternatively as the sister taxon to Polyglyphanodontia + Scleroglossa or as one of the sister taxa to the Mosasauria + Scleroglossa clade. The new finding, as well as other records from Argentina and Brazil, highlights a complex, still unrecovered, evolutionary history for lizards within the Mesozoic of South America.

Read the article »

Article DOI: 10.22179/REVMACN.23.716

Project DOI: 10.7934/P4059,
This project contains
  • 1 Media
  • 3 Documents
  • 1 Taxon
  • 1 Specimen
Total size of project's media files: 1.55M

Download Project SDD File
Currently Viewing:
MorphoBank Project 4059
  • Creation Date:
    24 July 2021
  • Publication Date:
    26 July 2021
  • Project views: 821

    Authors' Institutions

    • Museo Argentino de Ciencias Naturales Bernardino Rivadavia


    member name taxa specimens media media
    Martin Ezcurra
    Project Administrator

    Project has no matrices defined.

    Project views

    type number of views Individual items viewed (where applicable)
    Total project views821
    Project overview117
    Media views226Media search (194 views); M821734 (32 views);
    Documents list80
    Taxon list80
    Views for media list70
    Specimen list118

    Project downloads

    type number of downloads Individual items downloaded (where applicable)
    Total downloads from project28
    Document downloads6Martinelli et al 2021 Nexus data matrix (2 downloads); Martinelli et al 2021 TNT data matrix (2 downloads); Character labels and state descriptions (2 downloads);
    Project downloads22