Palaeohatteria Credner, and the Proganosauria

Abstract

ONE of the most important discoveries in Paleontology has just been made by Professor H. Oredner of Leipzig, well known by his publications on the Stegocephalia of the Permian of Saxony.* This discovery consists of a series of nearly complete skeletons of a reptile from the lower Permian (Rothliegendes). This reptile, with the exception of Stereosternum Oope, from the Oarboniferous (~) of Brazil, is the oldest yet known. Professor Oredner calls it Palmolwtteria from the close resemblance to EIatteria from New Zealand, the only living member of the Rhynchocephalia. But since Hatteria is preoccupied by Sphenodon, t this new form really ought to be called Palmosphenodon. It is placed by Professor Oredner among the Sphenodontidre, but it has-to be considered as the type of a distinct family, which may be called the Palmohatteriidm, or Palmosp!wnodontidm, in case the name PaZmosplu1nodon shall be admitted by Oredner. Clwr'(tcters if tlw Palmolwtteriidm. -Skull resembling Spltenodon,. lacrymal free from prrefrontal; bones showing centers of ossification, like those of Stegocephalia; interclavicle

Commentary: A Reassessment of the Taxonomic Position of Mesosaurs, and a Surprising Phylogeny of Early Amniotes

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The evolution of the scalation pattern in temnospondyl amphibians

“…The term ‘gastralia’ is often used to refer to the elongate ventral ossifications of basal tetrapods because their Λ‐shaped arrangement closely resembles the gastralia or ‘abdominal ribs’ of several amniotes. Indeed, the gastralia of amniotes are probably derived from the ventral scales of basal tetrapods (Baur, 1889; Voeltzkow & Döderlein, 1901; Romer, 1956). In extant crocodilians and Sphenodon , the gastralia develop in the dermis and become secondarily embedded in the rectus abdominis muscle later in ontogeny (Voeltzkow & Döderlein, 1901; Howes & Swinnerton, 1901; Claessens, 2004).…”

A reevaluation of early amniote phylogeny

“…Mesosauridae Baur 1889 Dejinition. The last common ancestor of Mesosaurus, Brazilosaurus and Stereosternum, This taxon is supported by eleven synapomorphies: 24* and all its descendants (Baur, 1889;Carroll, 1988;Lydekker, 1889).…”