Kuehneosauridae is an

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

family of small, lizard-like gliding

diapsid Diapsids ("two arches") are a clade of sauropsids, distinguished from more primitive eureptiles by the presence of two holes, known as temporal fenestrae, in each side of their skulls. The group first appeared about three hundred million years a ...

s known from the

Triassic The Triassic ( ) is a geologic period and system which spans 50.6 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.36 Mya. The Triassic is the first and shortest per ...

period of

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a Continent#Subcontinents, subcontinent of Eurasia ...

and

North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and th ...

. They are distinguished from other diapsids by their 'wings' formed by elongated ribs. These allowed the animal to glide and parachute similar to living gliding lizards. They were most likely insectivorous, judging from their pin-like teeth. They are often, but not always, placed in the group

Lepidosauromorpha Lepidosauromorpha (in PhyloCode known as ''Pan-Lepidosauria'') is a group of reptiles comprising all diapsids closer to lizards than to archosaurs (which include crocodiles and birds). The only living sub-group is the Lepidosauria, which cont ...

, though other studies have recovered them in other positions within

Sauria Sauria is the clade containing the most recent common ancestor of archosaurs (such as crocodilians, dinosaurs, etc.) and lepidosaurs ( lizards and kin), and all its descendants. Since most molecular phylogenies recover turtles as more closely ...

, including

Archosauromorpha Archosauromorpha (Greek for "ruling lizard forms") is a clade of diapsid reptiles containing all reptiles more closely related to archosaurs (such as crocodilians and dinosaurs, including birds) rather than lepidosaurs (such as tuataras, lizard ...

. The oldest and most primitive known member is ''

Pamelina ''Pamelina'' is an extinct genus of basal kuehneosaurid known from Early Triassic (Olenekian age) rocks of Czatkowice 1, Poland.. It was first named by Susan E. Evans in 2009 and the type species is ''Pamelina polonica''. It is the oldest known ...

'' from the

Early Triassic The Early Triassic is the first of three epochs of the Triassic Period of the geologic timescale. It spans the time between Ma and Ma (million years ago). Rocks from this epoch are collectively known as the Lower Triassic Series, which is ...

(

Olenekian In the geologic timescale, the Olenekian is an age in the Early Triassic epoch; in chronostratigraphy, it is a stage in the Lower Triassic series. It spans the time between Ma and Ma (million years ago). The Olenekian is sometimes divided i ...

stage) of

Poland Poland, officially the Republic of Poland, is a country in Central Europe. It is divided into 16 administrative provinces called voivodeships, covering an area of . Poland has a population of over 38 million and is the fifth-most populou ...

, which already has vertebrae with characteristics consistent with gliding or parachuting. ''

Icarosaurus ''Icarosaurus'' (meaning "Icarus lizard") is an extinct genus of kuehneosaurid reptile from the Late Triassic (Norian age) Lower Lockatong Formation of New Jersey.Berg, T.M., ''et al''. (1983). Stratigraphic Correlation Chart of Pennsylvania: G7 ...

'' is known from a single specimen from the

Carnian The Carnian (less commonly, Karnian) is the lowermost stage (stratigraphy), stage of the Upper Triassic series (stratigraphy), Series (or earliest age (geology), age of the Late Triassic Epoch (reference date), Epoch). It lasted from 237 to 227 m ...

-aged

Lockatong Formation The Triassic Lockatong Formation is a mapped bedrock unit in Pennsylvania, New Jersey, and New York. It is named after the Lockatong Creek in Hunterdon County, New Jersey. Description The Lockatong is defined as a light to dark gray, greenish-gra ...

New Jersey New Jersey is a state in the Mid-Atlantic and Northeastern regions of the United States. It is bordered on the north and east by the state of New York; on the east, southeast, and south by the Atlantic Ocean; on the west by the Delawa ...

. The

Late Triassic The Late Triassic is the third and final epoch of the Triassic Period in the geologic time scale, spanning the time between Ma and Ma (million years ago). It is preceded by the Middle Triassic Epoch and followed by the Early Jurassic Epoch ...

(

Norian The Norian is a division of the Triassic Period. It has the rank of an age ( geochronology) or stage (chronostratigraphy). It lasted from ~227 to million years ago. It was preceded by the Carnian and succeeded by the Rhaetian. Stratigraphic ...

stage) kuehneosaurids from

England England is a country that is part of the United Kingdom. It shares land borders with Wales to its west and Scotland to its north. The Irish Sea lies northwest and the Celtic Sea to the southwest. It is separated from continental Europe ...

, ''

Kuehneosaurus ''Kuehneosaurus'' is an extinct genus of Late Triassic kuehneosaurid reptile known from the Late Triassic (Norian stage) of the Penarth Group of southwest England and the Steinmergel Group of Luxembourg. Temperature at this stage and region w ...

'' and ''

Kuehneosuchus ''Kuehneosuchus'' is an extinct genus of Late Triassic kuehneosaurid reptile known from the Late Triassic (Norian stage) of southwest England. It was named by P. L. Robinson in 1967 and the type and only species is ''Kuehneosuchus latissimus ...

'', are very similar and can be distinguished from one another primarily on the length of their "wing" ribs, relatively short and massive in ''Kuehneosaurus'' but longer and more gracile in ''Kuehneosuchus. Kuehneosaurus'' was likely only capable of parachuting, while ''Kuehneosuchus'' could probably glide. ''

Rhabdopelix ''Rhabdopelix'' (meaning "rod pelvis") is a dubious genus of possible kuehneosaurid reptile, from the Late Triassic-age Lockatong Formation of Pennsylvania, USA. Based on partial, possibly chimeric remains, it was described by American na ...

'' may have been a kuehneosaurid; however, the fossils were lost, and the characteristics described are not entirely consistent with the other family members. The

cladogram A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to ...

below follows a 2009 analysis by paleontologists Susan E. Evans and Magdalena Borsuk−Białynicka.

References

Prehistoric reptile families Prehistoric lepidosauromorphs Triassic lepidosauromorphs Olenekian first appearances Norian extinctions Taxa named by Alfred Romer {{triassic-reptile-stub

See also

References