Lophostropheus Lophostropheus dinosaurs of the superfamily Coelophysoid

lofostrofej-lophostropheus-dinozavri-nadsemejstva.jpg

Lofostrophey (lat.: Lophostropheus) a genus of dinosaurs belonging to the superfamily Coelophysoidea (Coelophysoidea) from the suborder Theropoda (Theropoda) and lived about 200 million years ago, at the end of the Triassic the beginning of the Jurassic period, on the territory of modern France, in Normandy. Its only species known to science is Lophostropheus airelensis.

Lophostropheus is the only late Triassic-early Jurassic theropod known from well-preserved remains, and one of the few dinosaurs that may have survived the Triassic-Jurassic extinction event. It was a small or medium-sized terrestrial “two-legged” predator of moderate build, the length of which could reach 3 meters.

For many years, this dinosaur was erroneously classified first as a halticosaurus (lat.: Halticosaurus), then as Liliensternus, but later recognized as a new genus and reclassified as lofostrophey in 2007.

Name etymology

The Latin generic name “Lophostropheus” is formed from the Greek words “λόφος” (lophos; “comb”) and “στροφή” (stanza; “vertebrae”) and can be roughly translated into Russian as “having ridge-shaped vertebrae”. It indicates the presence of protruding upper and lower lamellar outgrowths on the cervical vertebrae of this dinosaur.

The specific epithet “airelensis” indicates the area (Erel quarry, fr.: carrière d’Airel), where the remains of an individual of this species of lophostrophy were found. The type species Lophostropheus airelensis was scientifically described in 2007. The authors of the description and species name are the Argentine paleontologist Martin Escurra and his French colleague Gilles Cuny.

Description

It is assumed that the maximum body length of lophostropheus reached 3 meters with a mass of up to 100 kg. This assumption is based on the size of a fragmentary skeleton described in 1966 as a specimen of halticosaurus.

The dinosaur remains specimen consists of 1 tooth, 5 cervical vertebrae, 2 dorsal vertebrae, 4 sacral vertebrae, tail vertebrae, fragments of all the bones of the pelvis, as well as another unidentified fragment and is currently stored in the collection of the University of Caen in Lower Normandy without an inventory number.

Distinguishing anatomical features

Lophostropheus differs from other theropods in several ways. In particular, some of its features, such as the presence of a spherical connection with the anterior part of its cervical vertebrae, a nested connection with the anterior part of the caudal vertebrae, as well as a vertical ridge on its ilium, bring it closer to the more highly developed (derivative) representatives of this suborder. However, all these properties are interpreted as convergences.

In addition, unlike lilienstern, the cervical vertebrae of the dinosaur have protruding ridges above and below (the presence of which it owes its generic name), and inside the cervical vertebrae there is an additional pair of air cavities.

Lophostropheus was closer in comparison with Liliensterne kinship with representatives of the Coelophyside family (lat.: Coelophysidae), including the well-known coelophysis (Coelophysis). An analysis of the anatomical features of lophostropheus, the totality of which distinguishes it from all other animals, showed that some, although not all, of the analyzed features are autapomorphic, i.e.,.e. unique to this genus.

According to Eskurra and Cuny, lophostrophy is distinguished by the following features:

  • a moderately convex anterior articular surface of the anterior postaxial cervical vertebrae (also present in ceratosaurs and tetanurians);
  • a large oval-shaped lateral fossa (also seen in Herrerasaurus) in the center of the last dorsal vertebra;
  • the hyposphene of the last dorsal vertebra, considerably elongated in the dorsoventral direction;
  • an incipient concavity on the articular surface of the posterior group of the upper cervical vertebrae (also present in ceratosaurs and tetanurians);
  • the same length of all tail vertebrae (as in Dilophosaurus)
  • Classification

    In 1966 French paleontologists K. Larsonner and Albert-Felix de Lapparan described a fragmentary skeleton of an unknown theropod dinosaur of the late Triassic early Jurassic period found in Normandy as belonging to an individual of a halticosaurus.

    In 1933, Gilles Cuny and Peter Golton reclassified the found dinosaur as a representative of a new species belonging to the famous genus Lilienstern, and named it Liliensternus airelensis. However, other researchers began to note differences between the species Liliensternus airelensis and the type species Liliensternus liliensterni, consisting, for example, in a different number of air cavities in the cervical vertebrae of these animals.

    Therefore, in 2007, Martin Escurra and Gilles Cuny identified an unknown theropod in a separate genus Lophostropheus.

    Rating
    ( No ratings yet )
    Leave a Reply

    ;-) :| :x :twisted: :smile: :shock: :sad: :roll: :razz: :oops: :o :mrgreen: :lol: :idea: :grin: :evil: :cry: :cool: :arrow: :???: :?: :!: