Share. Avemetatarsalia). The final unambiguous members of Archosauromorpha represent the most controversial group. Die entsprechende Schwestergruppe der Archosauromorpha sind die Lepidosauromorpha. Innerhalb Lepidosauromorpha gibt es ausgestorbene Gruppen wie Sauropterygios, darunter Meeresreptilien wie Mosasaurus, ... Daher gibt es in Archosauromorpha eine der unglaublichsten Entwicklungen und Veränderungen in einer Reihe von Tieren, die die Erde fast 200 Millionen Jahre lang dominierten. The name was coined by Benton (1983) to include the lepidosaurs and sauropterygians in a higher taxon. Ezcurra (2016) argued that presence of supratemporal fossae and an absence or poor development of the sagittal crest could be used to characterize Crocopoda. Archosauromorpha is similar to these species: Reptile, Archosaur, Lepidosauromorpha and more. Likewise, extinct turtle relatives known as Pantestudines would also fall within Archosauromorpha. Choristoderes share numerous otherwise unique traits with archosauromorphs, but they share an equal or greater number of unique traits with lepidosauromorphs as well, so there is still some debate over their inclusion within either group. Since Pantestudines may encompass the entire aquatic reptile order Sauropterygia, this means that Archosauromorpha (as Archelosauria) may be a much wider group than commonly believed. Click on an image to view larger version & data in a new window . Schwestergruppe der Lepidosauromorpha sind die Archosauromorpha. Lepidosauromorphs have remained cold blooded because of their low-energy sprawling stance. On the other hand, the rear branch jugal bone lengthens to fill some of the space left by the shortening of the anterior process of the quadratojugal. Schwestergruppe der Lepidosauromorpha sind die Archosauromorpha. Trilophosaurids and azendohsaurids are now united under the group Allokotosauria ("strange reptiles"). These were the Archosauriformes, a diverse assortment of animals including the famous dinosaurs and pterosaurs. Die Archosauromorpha sind eine Verwandtschaftsgruppe der diapsiden Reptilien, der die Archosaurier und verschiedene ausgestorbene Reptiliengruppen angehören, die enger mit den Archosauriern als mit den Lepidosauriern verwandt sind. The Archosauromorpha, including Archosauriformes. The bones surrounding the quadratojugal also reconfigure to offset the changes to the quadratojugal. INTRODUCTION TO THE CLASS LEPIDOSAUROMORPHA. These include laminae on the vertebrae, a posterodorsal process of the premaxilla, a lack of notochordal canals, and the loss of the entepicondylar foramen of the humerus. The calcaneum, for example, has a tube-like outer extension known as a calcaneal tuber in certain archosauromorphs. [2] As such, this final group of Archosauromorpha is generally considered paraphyletic or polyphyletic, and few modern studies use it. The Archosauromorpha, including Archosauriformes. In many advanced archosauromorphs, the capitullum and trochlea (elbow joints) of the humerus are poorly developed. The centrum (main body) of each vertebra is parallelogram-shaped, with a front surface typically positioned higher than the rear surface. The only living sub-group is the Lepidosauria: extant lizards, snakes and tuataras. Topic. In many long-necked archosauromorphs, the rib facets are slanted, connecting to cervical ribs that are often long, thin, and dichocephalous (two-headed). [14], Although the most diverse clade of living archosauromorphs are birds, early members of the group were evidently reptilian, superficially similar to modern lizards. This page was last edited on 29 November 2020, at 04:00. Since the seminal studies of the 1980s, Archosauromorpha has consistently been found to contain four specific reptile groups, although the definitions and validity of the groups themselves have been questioned. [15], Thin, plate-like ridges known as laminae develop to connect the vertebral components, sloping down from the elongated transverse processes to the centra. As for the nares themselves, they were generally large and oval-shaped, positioned high and close to the midline of the skull. [2], The ankle bones of archosauromorphs tend to acquire complex structures and interactions with each other, and this is particularly the case with the large proximal tarsal bones: the astragalus and calcaneum. He argued that Prolacerta was much closer to Archosauriformes than to other "prolacertiforms", invalidating the name. [8] Likewise, Pamelaria is now considered an allokotosaur, Macrocnemus is a tanystropheid, and Protorosaurus may be too basal ("primitive") to form a clade with any of its supposed close relatives. [6][2] The chameleon- or tamandua-like drepanosaurs are also semi-regularly placed within Archosauromorpha,[8] although some studies have considered them to be part of a much more basal lineage of reptiles. Gauthier used the name Archosauria to refer to what is now called the Archosauriformes; in modern studies, the name Archosauria has a more restricted definition that only includes the ancestors of crocodilians (i.e. Innerhalb Lepidosauromorpha gibt es ausgestorbene Gruppen wie Sauropterygios, darunter Meeresreptilien wie Mosasaurus, ... Daher gibt es in Archosauromorpha eine der unglaublichsten Entwicklungen und Veränderungen in einer Reihe von Tieren, die die Erde fast 200 Millionen Jahre lang dominierten. Other notable genera include Boreopricea, Pamelaria, and Macrocnemus, as well as strange gliding reptiles such as Sharovipteryx and Mecistotrachelos. A landmark 1998 study by David Dilkes completely deconstructed the concept of Prolacertiformes as a traditional monophyletic group (i.e. [2] But, archosaurs have a gizzard while tortoises and turtles do not. This page deals mostly with the phylogeny between the various stem-diapsids, Lepidosauromorpha and Archosauromorpha. Two subclades of Archosauriformes survive to the present day: the semiaquatic crocodilians and the last of the feathered dinosaurs: birds. [2], The lower temporal fenestra is not fully enclosed in early archosauromorphs (and choristoderes) due to alterations to the structure of the quadratojugal bone at the rear lower corner of the skull. [2], For an explanation of very similar terms, see, "The phylogenetic relationships of basal archosauromorphs, with an emphasis on the systematics of proterosuchian archosauriforms", "The Origin and Early Evolution of Sauria: Reassessing the Permian Saurian Fossil Record and the Timing of the Crocodile-Lizard Divergence", "Amniote phylogeny and the importance of fossils", "Classification and phylogeny of the diapsid reptiles", "The early history and relationships of the Diapsida", "A bird-like skull in a Triassic diapsid reptile increases heterogeneity of the morphological and phylogenetic radiation of Diapsida", "An archosaur-like laterosphenoid in early turtles (Reptilia: Pantestudines)", https://en.wikipedia.org/w/index.php?title=Archosauromorpha&oldid=991260479, Creative Commons Attribution-ShareAlike License.