Re-evaluation of the historic Canadian fossil Bathygnathus borealis from the Early Permian of Prince Edward Island

  title={Re-evaluation of the historic Canadian fossil Bathygnathus borealis from the Early Permian of Prince Edward Island},
  author={Kirstin S. Brink and Hillary C. Maddin and David C Evans and Robert R. Reisz},
  journal={Canadian Journal of Earth Sciences},
The holotype and only known specimen of Bathygnathus borealis is a partial snout with maxillary dentition of a presumed sphenacodontid from the Lower Permian (Artinskian 283–290 Ma) redbeds of Prince Edward Island, Canada. Due to its incomplete nature, assessment of the taxon’s systematic position within a cladistic analysis had never been performed. However, recent recognition of the phylogenetic utility of tooth characters in sphenacodontids now allows for a modern phylogenetic evaluation of… 

Re-evaluation of an early sphenacodontian synapsid from the Lower Permian of England

  • F. Spindler
  • Geography, Environmental Science
    Earth and Environmental Science Transactions of the Royal Society of Edinburgh
  • 2020
The holotypic isolated maxilla of the early sphenacodontian Haptodus grandis from the Cisuralian of England is revisited and reveals a mosaic distribution of maxillary features, most significantly regarding the precanine region.

Dimetrodon (Synapsida: Sphenacodontidae) from the cave system at Richards Spur, OK, USA, and a comparison of Early Permian–aged vertebrate paleoassemblages

The morphology and histology of a small neural spine with the distinctive figure-8 shape attributable to Dimetrodon is described for the first time, suggesting not only that this animal was more widespread than previously thought, but that there are different patterns of Early Permian synapsid evolution in different ecological settings.

A re-assessment of the oldest therapsid Raranimus confirms its status as a basal member of the clade and fills Olson’s gap

CT scanning techniques are used to digitally reconstruct the bones and trigeminal canals of the snout of Raranimus in 3D and confirm that RarAnimus shares a high number of synapomorphies with more derived therapsids and is the only theraptor known so far to display a “pelycosaur”-like maxillary canal bearing a long caudal alveolar canal that gives off branches at regular intervals.

Comment (Case 3695) — Support for the proposed conservation of Dimetrodon Cope, 1878 by reversal of precedence with Bathygnathus Leidy, 1853 (Synapsida: Sphenacodontidae)

  • S. Lucas
  • Biology
    The Bulletin of Zoological Nomenclature
  • 2017
The Commission is urged to accept Brink’s (2015) application by giving Dimetrodon Cope, 1878 precedence over Bathygnathus Leidy, 1853 whenever the two are considered synonyms.

A new varanopid synapsid from the early Permian of Oklahoma and the evolutionary stasis in this clade

A new varanopid taxon is reported, represented by substantially more complete material, which supports the placement of this taxon within Mesenosaurus, as a new species, Me. efremovi.

Convergent dental adaptations in the serrations of hypercarnivorous synapsids and dinosaurs

The same denticles and interdental folds form the cutting edges in the teeth of a Permian gorgonopsian synapsid, extending the temporal and phylogenetic distribution of this dental morphology and demonstrating that the first iteration of this feature appeared in non-mammalian synapsids.

Case 3695 Dimetrodon Cope, 1878 (Synapsida, sphenacodontidae): proposed conservation by reversal of precedence with Bathygnathus Leidy, 1853

  • K. Brink
  • Biology
    The Bulletin of Zoological Nomenclature
  • 2015
It is proposed that Dimetrodon be given precedence over Bathygnathus whenever these names are considered to be synonyms, which has become widely accepted and is in prevailing usage.


Abstract Four substantial tetrapod extinctions have been identified during the Permian, but only one of these is an apparent mass extinction. Analyses of global compilations of the family-level

Permian tetrapod biochronology, correlation and evolutionary events

  • S. Lucas
  • Geography, Environmental Science
    Special Publications
  • 2017
Abstract The most extensive Permian tetrapod (amphibian and reptile) fossil records from the western USA (New Mexico to Texas) and South Africa have been used to define 11 land vertebrate faunachrons

Exact distribution of divergence times from fossil ages and tree topologies

This work suggests an older age for Amniota (the synapsid/sauropsid or bird/mammal divergence) than has been assumed by most studies that have used this constraint and provides, for the first time, a method to compute the shape of the probability density for this divergence time.



A New Basal Sphenacodontid Synapsid from the Late Carboniferous of the Saar-Nahe Basin, Germany

A new basal sphenacodontid synapsid, represented by an anterior portion of a mandible, demonstrates for the first time the presence of amniotes in the largest European Permo-Carboniferous basin, the

Evidences of Theriodonts in Permian Deposits elsewhere than in South Africa

  • Owen
  • Geography
    Quarterly Journal of the Geological Society of London
  • 1876
A few days ago Mr. W. Davies brought to my notice the cast of a fossil which had been purchased by the British Museum in 1865 of Krantz, the dealer, with the label ‘Eurosaurus uralensis, H. v. Meyer,

The Sphenacodontid Synapsid Neosaurus cynodus, and Related Material, from the Permo-Carboniferous of France

Sphenacodontid synapsids were major components of early Permian ecosystems. Despite their abundance in the North American part of Pangaea, they are much rarer in Europe. Among the few described


Abstract:  Early Permian terrestrial vertebrate faunal assemblages of Laurasia are dominated by large ophiacodontid, sphenacodontid, and edaphosaurid synapsids. This pattern contrasts with the fauna

Amniote faunal revision of the Pictou Group (Permo-Carboniferous), Prince Edward Island, Canada

New Basal Synapsid Supports Laurasian Origin for Therapsids

A new large predatory synapsid, Raranimus dashankouensis gen. et sp.

First record of plicidentine in Synapsida and patterns of tooth root shape change in Early Permian sphenacodontians

Recent histological studies have revealed a diversity of dental features in Permo-Carboniferous tetrapods. Here, we report on the occurrence of plicidentine (infolded dentine around the base of the

On the Remains of a Reptile (Dendrerpeton Acadianum, Wyman and Owen) and of a Land Shell discovered in the Interior of an Erect Fossil Tree in the Coal Measures of Nova Scotia

  • C. LyellJ. Dawson
  • Environmental Science
    Quarterly Journal of the Geological Society of London
  • 1853
Descriptions and sections of the Coal-formation of Nova Scotia, and particularly of the cliffs called the South Joggins, have been published by Messrs. Jackson and Alger*, Mr. Brown†, Dr. Gesner‡,

New occurrences of Ichniotherium and Striatichnium from the Lower Permian Kildare Capes Formation, Prince Edward Island, Canada: palaeoenvironmental and biostratigraphic implications

Abstract:  Tracks and trackways of the vertebrate ichnotaxon Ichniotherium sphaerodactylum and a trace of the invertebrate ichnotaxon Striatichnium bromackerense are described for the first time in

Hidden dental diversity in the oldest terrestrial apex predator Dimetrodon.

A time-calibrated phylogenetic analysis indicates that changes in dental morphology occur in the absence of any significant changes in skull morphology, suggesting that the morphological change is associated with changes in feeding style and trophic interactions in these ecosystems.