Scleromochlus taylori and the origin of dinosaurs and pterosaurs

  title={Scleromochlus taylori and the origin of dinosaurs and pterosaurs},
  author={Michael J. Benton},
  journal={Philosophical Transactions of the Royal Society B},
  • M. Benton
  • Published 29 August 1999
  • Biology
  • Philosophical Transactions of the Royal Society B
The phylogenetic position of Scleromochlus taylori has been disputed recently, in terms of whether it is a basal sister group of Pterosauria or of Dinosauromorpha. The seven specimens, all from the Lossiemouth Sandstone Formation (late Carnian, Late Triassic) of Lossiemouth, near Elgin, north–east Scotland, suggest that Scleromochlus shares no unique features with either Pterosauria or Dinosauromorpha, together the Ornithodira, but is a close outgroup. Scleromochlus retains a primitive ankle… 

Ornithosuchidae: a group of Triassic archosaurs with a unique ankle joint

The presence of derived pseudosuchians in the late Olenekian produces a ghost lineage of c.

The osteology and relationships of Vancleavea campi (Reptilia: Archosauriformes)

Vancleavea campi from the Late Triassic of western North America, represents the latest surviving non-archosaurian archosauriform known to date and is found to be more closely related to Archosauria than both Erythrosuchus and Proterosuchus, but outside of the crown group.

A Phylogenetic Analysis of the Basal Ornithischia (Reptilia, Dinosauria)

A phylogenetic analysis of 19 taxonomic units, including two outgroup taxa, produced four most parsimonious trees and a bootstrap analysis was performed to determine the relative support for the resultant phylogeny.

A tiny ornithodiran archosaur from the Triassic of Madagascar and the role of miniaturization in dinosaur and pterosaur ancestry

Analysis of ancestral body size indicates that there was a pronounced miniaturization event near the common ancestor of dinosaurs and pterosaurs, and an analysis of body size evolution in dinosaurs and other archosaurs demonstrates that the earliest-diverging members of the group may have been smaller than previously thought.

Early dinosaurs: A phylogenetic study

A new cladistic analysis of the early dinosaur radiation was performed to assess the relationships among the three major clades (Ornithischia, Sauropodomorpha and Theropoda) and to define the phylogenetic position of the basal members of the group.

Triassic pterosaurs

Abstract Pterosaurs are a clade of highly specialized, volant archosauromorphs recorded from the Upper Triassic to the uppermost Cretaceous. Problematic remains referred to the Pterosauria are

The anatomy and phylogenetic position of the Triassic dinosaur Staurikosaurus pricei Colbert, 1970

The phylogenetic position of S. pricei is constrained by that of its sister taxon H. ischigualastensis, which is known from much more complete material, and the absence of some characters observed in the clades Theropoda and Sauropodomorpha suggests that S.pricei is not a member of Eusaurischia.

Palaeobiology, Morphology, and Flight Characteristics of Pterodactyloid Pterosaurs

The “crocodilian-like” sequence of suture closure between the neural arches and vertebral bodies of the thoracic vertebrae is confirmed within the azhdarchoid pterosaurs, indicating that the developmental timing between the Azhdarchoidea and Ornithocheiroidea did not significantly differ.

The earliest bird-line archosaurs and the assembly of the dinosaur body plan.

It is demonstrated that several anatomical features long thought to characterize Dinosauria and dinosauriforms evolved much earlier, soon after the bird-crocodylian split, and that the earliest avemetatarsalians retained the croc Codylian-like ankle morphology and hindlimb proportions of stem archosaurs and early pseudosuchians.


Abstract Re-examination of the surviving specimens of Thecodontosaurus antiquus indicates that this plesiomorphic sauropodomorph can be diagnosed on the basis of elongate basipterygoid processes, a



The phylogenetic position of the Pterosauria within the Archosauromorpha

A cladistic analysis of the Archosauromorpha using characters presented by previous workers results in a single most parsimonious tree with the Pterosauria as the major sister- group of the Dinosauria, but that sister-group relationship is supported only by a suite of hindlimb characters that are correlated with bipedal digitigrade locomotion in dinosaurs.

Phylogeny of the Crocodylotarsi, with reference to archosaurian and crurotarsan monophyly

The phylogeny of the Crocodylotarsi was re-examined based on study of most relevant fossil material of the early non–crocodyliform members of the clade.

Dinosaurian precursors from the Middle Triassic of Argentina: Marasuchus lilloensis, gen. nov.

Several synapomorphies unite Marasuchus and dinosaurs (as Dinosauriformes) to the exclusion of the contemporary dinosauromorph Lagerpeton and pterosaurs.

On a New Dinosaurian Reptile (Scleromochlus Taylori, gen. et sp. nov.) from the Trias of Lossiemouth, Elgin

  • A. Woodward
  • Geology
    Quarterly Journal of the Geological Society of London
  • 1907
Althought so many types of reptiles have been obtained during recent years from the Triassic sandstones of Elgin, Mr. William Taylor has lately discovered two examples of a new form which represents

Triassic reptiles from the elgin area: Stagonolepis, Dasygnathus and their allies

  • A. D. Walker
  • Environmental Science
    Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences
  • 1961
It is suggested that a trend towards the reduction of the anterior pterygoid muscle took place in aetosaurids, in parallel with a similar trend in ornithischian dinosaurs.

Dinosaurian precursors from the Middle Triassic of Argentina: Lagerpeton chanarensis

There is no evidence that Lagerpeton and other small-bodied dinosauromorphs in the Los Chanares fauna, namely “Lagosuchus” lilloensis, comprise a monophyletic group.

The skull and neck of the basal theropod Herrerasaurus ischigualastensis

The skull of Herrerasaurus ischigualastensis has a rectangular profile and a transversely narrow snout and other features of the skull constitute dinosaurian synapomorphies, such as the loss of the postfrontal and small post-temporal opening.

Basal Archosaurs: Phylogenetic Relationships and Functional Implications

Erect posture has been identified as the key adaptation (possibly associated with locomotor stamina) that resulted in the archosaurian radiation.

The pectoral girdle and forelimb of the basal theropod Herrerasaurus ischigualastensis

ABSTRACT New specimens of Herrerasaurus ischigualastensis shed light on the structure and function of the pectoral girdle and forelimb in early theropod dinosaurs. As in tetanurian theropods, the

The Complete Skull and Skeleton of an Early Dinosaur

Fossils of Herrerasaurus and younger dinosaurs from Upper Triassic beds in Argentina suggest that the dinosaurian radiation was well under way before dinosaurs dominated terrestrial vertebrate communities in taxonomic diversity and abundance.