Is Proterosuchus a dinosaur?

How did Erpetosuchus look like a crocodile?

Aside from the shape of its head, though, Erpetosuchus didn’t much resemble modern crocodiles in either appearance or behavior; it may have run quickly on its two hind feet (rather than crawling on all fours like modern crocodiles), and probably subsisted on insects rather than red meat. PLOS /Wikimedia Commons/CC BY 4.0

What are the differences between archosaurs and crocodiles?

Archosaurs, the crocodile’s oldest relative, were among the many plant-eating dinos that thrived during this period. Archosaurs looked very much like crocodiles, except that their nostrils were positioned on the tops of their heads rather than the tips of their snouts.

What are the characteristics of Protosuchus richardsoni?

Protosuchus richardsoni fossil AMNH 3024. As an early crocodile relative, its skull featured more crocodilian characteristics than its earlier ancestors; it had short jaws that broadened out at the base of the skull, providing a large surface to which its jaw muscles could attach.

What is the difference between lepidosaurs and archosaurs?

Lepidosaurs include snakes, tuataras, lizards whereas, archosaurs include crocodiles and birds. The origin of amphibians lies about 350 million ago.

What is Erpetosuchus?

Erpetosuchus is an extinct genus of pseudosuchian from the Late Triassic. The type species of Erpetosuchus is E. granti. It was first described by E. T. Newton in 1894 for remains found in northeastern Scotland, including four specimens from the latest Carnian Lossiemouth Sandstone Formation.

How did paleontologists determine that Gracilisuchus was a crocodile?

On further analysis, though, paleontologists realized they were looking at a (very early) crocodile, based on subtle anatomical features of Gracilisuchus’ skull, spine and ankles.

Is Protosuchus a crocodile?

It’s one of the ironies of paleontology that the earliest reptile to be conclusively identified as a prehistoric crocodile lived not in the water, but on the land. What puts Protosuchus firmly in the crocodile category are its well-muscled jaws and sharp teeth, which interlocked firmly when its mouth was closed.

What is the name of the earliest reptile?

1 Raranimus. “Diagnosed” in 2009 on the basis of a single, partial skull, Raranimus may prove to be the earliest therapsid (mammal-like reptile) yet discovered — and since therapsids were directly … 2 Thrinaxodon. Thrinaxodon. … 3 Tiarajudens. Tiarajudens. … 4 Titanosuchus. Titanosuchus. … 5 Trirachodon. Trirachodon. … 6 Ulemosaurus.

What are the characteristics of a crocodile dentition?

The dentition of the animal also resembled modern crocodiles, including the teeth in the lower jaw that fitted into notches on either side of the upper jaw when the mouth was closed. It also possessed a powerful tail which later developed into a propulsion mechanism through water in its descendants.

What is Lepidosauria?

The Lepidosauria (from Greek meaning scaled lizards) are reptiles with overlapping scales. This subclass includes Squamata and Rhynchocephalia.

Are Testudines related to Lepidosauria?

Testudines (turtles) may be related to lepidosaurs or to archosaurs, but no consensus has been reached on this subject. Lepidosauria is encompassed by Lepidosauromorpha, a broader group defined as all reptiles (living or extinct) closer to lepidosaurs than to archosaurs.

What kind of skin does a crocodile have?

Crocodiles have smooth skin on their bellies and sides, while their dorsal surfaces are armoured with large osteoderms. The armoured skin has scales and is thick and rugged, providing some protection. They are still able to absorb heat through this armour, as a network of small capillaries allows blood through the scales to absorb heat.

What type of animal is Gracilisuchus?

Gracilisuchus (meaning “slender crocodile”) is an extinct genus of tiny pseudosuchian (a group which includes the ancestors of crocodilians) from the Late Triassic of Argentina. It contains a single species, G. stipanicicorum, which is placed in the clade Suchia, close to the ancestry of crocodylomorphs.

What is the name of the first crocodile?

The name Protosuchus means “first crocodile”, and is among the earliest animals that resemble crocodilians. Protosuchus was about 1 metre (3.3 ft) in length and about 40 kilograms (88 lb) in weight.

What are the characteristics of crocodile teeth?

A crocodile often has differently shaped teeth, which can range from blunt to pointed, almost needle-like silhouettes. In general, these characteristics vary in each species, but a pattern is followed in which reptiles with narrow snouts have the most uniform teeth.

What is the sister taxon to Lepidosauria?

Purely in the context of modern taxa, Lepidosauria can be considered the sister taxon to Archosauria, which includes Aves (birds) and Crocodilia. Testudines (turtles) may be related to lepidosaurs or to archosaurs, but no consensus has been reached on this subject.

Is a tuataras a lepidosaur?

Tuataras and the squamates comprise the Lepidosauria. Represented by only two species on islands off the coast of New Zealand, the lizard-like tuataras ( Fig. 1.3) diverged early within the lepidosaurian clade. Lizards, snakes, and amphisbaenians comprise the Squamata.

What is a Lepidosauria?

Lepidosauria is an ancient group with fossil lizards known from the Upper Permian (approximately 250 mybp) and sphenodontids from the Triassic ( Estes, 1983; Carroll, 1988b ).

What is the most recent common ancestor of Lepidosauria and archosaurians?

Sauria is the most recent common ancestor of Lepidosauria and Archosauria, and all of that ancestor’s descendants. Sauria is diagnosed by the presence of a specialized ankle joint, long and generally slender hind limbs, and relatively larger leg muscles.

Are Testudines related to lepidosaurs?

Testudines (turtles) may be related to lepidosaurs or to archosaurs, but no consensus has been reached on this subject. Lepidosauria is encompassed by Lepidosauromorpha, a broader group defined as all reptiles (living or extinct) closer to lepidosaurs than to archosaurs.

How are Lepidosauria different from other reptiles?

The reptiles in the subclass Lepidosauria can be distinguished from other reptiles by a variety of characteristics. First, the males have evolved a hemipenis instead of a single penis with erectile tissue that is found in crocodilians, birds, mammals, and turtles.