Euparkeriidae is a family of small basal

Basal (phylogenetics)

In phylogenetics, a basal clade is the earliest clade to branch in a larger clade; it appears at the base of a cladogram.A basal group forms an outgroup to the rest of the clade, such as in the following example:...

 archosauromorph carnivore

Carnivore

A carnivore meaning 'meat eater' is an organism that derives its energy and nutrient requirements from a diet consisting mainly or exclusively of animal tissue, whether through predation or scavenging...

s which lived from the Early Triassic

Triassic

The Triassic is a geologic period and system that extends from about 250 to 200 Mya . As the first period of the Mesozoic Era, the Triassic follows the Permian and is followed by the Jurassic. Both the start and end of the Triassic are marked by major extinction events...

 to the Middle Triassic (Anisian

Anisian

In the geologic timescale, the Anisian is the lower stage or earliest age of the Middle Triassic series or epoch and lasted from 245 million years ago until 237 million years ago, approximately...

). Their fossil remains are known so far from South Africa and Russia. Quite opposite to their sister family Erythrosuchidae

Erythrosuchidae

Erythrosuchidae are a family of large basal archosauromorph carnivores that lived from the later Early Triassic to the early Middle Triassic . Their fossil remains are known so far from South Africa , the Perm region of Russia, and China...

, euparkeriids were small, slender animals which were probably facultative bipeds.

The clade

Clade

A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...

 is named after Euparkeria

Euparkeria

Euparkeria was a small African reptile of the early Triassic period between 248-245 million years ago, close to the ancestry of the archosaurs.- Palaeobiology :...

, a relatively well-known member of the group. Other possible euparkeriids include Dorosuchus

Dorosuchus

Dorosuchus is an extinct genus of archosauriform that is possibly a member of the family Euparkeriidae. It lived during the Anisian stage of the Middle Triassic. Fossil material is known from Sol-Iletsk in Orenburg Oblast, Russia. The type species is D...

, Halazaisuchus, Osmolskina

Osmolskina

Osmolskina is a genus of archosauriform reptile which lived during the Early Triassic in what is now Poland. The type species, Osmolskina czatkowicensis, was described by Magdalena Borsuk−Białynicka and Susan Evans in 2003. The generic name honors the late female Polish paleontologist Halszka...

, Wangisuchus, and Xilousuchus

Xilousuchus

Xilousuchus is an extinct genus of poposauroid from lower Triassic deposits of Fugu County of northeastern Shanxi Province, China. It is known from the holotype, IVPP V 6026, a single well-preserved partial skeleton including the skull. It was found from the Heshanggou Formation of the...

. The family name was first proposed by Friedrich von Huene

Friedrich von Huene

Friedrich von Huene was a German paleontologist who named more dinosaurs in the early 20th century than anyone else in Europe.-Biography:...

 in 1920; Huene classified euparkeriids as members of Pseudosuchia

Pseudosuchia

Pseudosuchia is the name originally given to a group of prehistoric reptiles from the Triassic period. The name has been variously interpreted, and it is still sometimes, if infrequently, used in scientific literature today. A more commonly used name, Crurotarsi, is often substituted for...

. More recent analysis places Euparkeriidae within Archosauriformes

Archosauriformes

Archosauriformes is a clade of diapsid reptiles that developed from archosauromorph ancestors some time in the Late Permian...

. Euparkeriids lie close to the ancestry of the crocodiles, pseudosuchians, ornithodires and dinosaur

Dinosaur

Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...

s, but are not considered directly ancestral.

External links

• Euparkeriidae from Palaeos.com (technical)