Monofenestrata is an unranked group of

pterosaur Pterosaurs (; from Greek ''pteron'' and ''sauros'', meaning "wing lizard") is an extinct clade of flying reptiles in the order, Pterosauria. They existed during most of the Mesozoic: from the Late Triassic to the end of the Cretaceous (228 to ...

s that includes the family

Wukongopteridae Wukongopteridae is a group of basal pterosaurs, found in China and the UK. It contains eight species in five genera, all dated to the Middle to Late Jurassic period, The Wukongopteridae were first named by Wang ''et al.'' in 2009, not yet givin ...

and the suborder

Pterodactyloidea Pterodactyloidea (derived from the Greek words ''πτερόν'' (''pterón'', for usual ''ptéryx'') "wing", and ''δάκτυλος'' (''dáktylos'') "finger" meaning "winged finger", "wing-finger" or "finger-wing") is one of the two traditional ...

. The

clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...

Monofenestrata was in 2009/2010 defined as the group consisting of ''

Pterodactylus ''Pterodactylus'' (from Greek () meaning 'winged finger') is an extinct genus of pterosaurs. It is thought to contain only a single species, ''Pterodactylus antiquus'', which was the first pterosaur to be named and identified as a flying rept ...

'' and all species sharing with ''Pterodactylus'' the

synapomorphy In phylogenetics, an apomorphy (or derived trait) is a novel character or character state that has evolved from its ancestral form (or plesiomorphy). A synapomorphy is an apomorphy shared by two or more taxa and is therefore hypothesized to have ...

of an external nostril confluent with the

antorbital fenestra An antorbital fenestra (plural: fenestrae) is an opening in the skull that is in front of the eye sockets. This skull character is largely associated with archosauriforms, first appearing during the Triassic Period. Among extant archosaurs, bird ...

, the major skull opening on the side of the snout. The name is derived from

Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...

''monos'', "single", and

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

''fenestra'', "window". The concept was inspired by the discovery of ''

Darwinopterus ''Darwinopterus'' (meaning "Darwin's wing") is a genus of pterosaur, discovered in China and named after biologist Charles Darwin. Between 30 and 40 fossil specimens have been identified, all collected from the Tiaojishan Formation, which dates t ...

'', a species combining a pterodactyloid-type skull with a more basal build of the remainder of the body. The Darwinoptera, a primitive subgroup of monofenestratans showing this transitional anatomy, was also named for ''Darwinopterus'' and defined as all descendants of its common ancestor with '' Pterorhynchus''. The earliest known monofenestratan fossils have been found in the Stonesfield Slate formation of the

United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the continental mainland. It comprises England, Scotland, Wales and North ...

, which dates to the

Bathonian In the geologic timescale the Bathonian is an age and stage of the Middle Jurassic. It lasted from approximately 168.3 Ma to around 166.1 Ma (million years ago). The Bathonian Age succeeds the Bajocian Age and precedes the Callovian Age. Strat ...

stage of the

Middle Jurassic The Middle Jurassic is the second epoch of the Jurassic Period. It lasted from about 174.1 to 163.5 million years ago. Fossils of land-dwelling animals, such as dinosaurs, from the Middle Jurassic are relatively rare, but geological formations co ...

, dated to about 166 million years ago. Identified elements include cervical vertebrae, fourth metacarpals and a possible pterodactyloid synsacrum. Michael O’Sullivan; David M. Martill (2018). "Pterosauria of the Great Oolite Group (Bathonian, Middle Jurassic) of Oxfordshire and Gloucestershire, England". Acta Palaeontologica Polonica. Online edition. . Below is a

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 d ...

showing the results of a

phylogenetic In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ...

analysis presented by Andres, Clark & Xu, 2014. This study found the two traditional groupings of ctenochasmatoids and kin as an early branching group (represented as the group

Archaeopterodactyloidea Archaeopterodactyloidea (meaning "ancient Pterodactyloidea") is an extinct clade of pterodactyloid pterosaurs that lived from the middle Late Jurassic to the latest Early Cretaceous periods (Kimmeridgian to Albian stages) of Africa, Asia, Europe ...

), with all other pterodactyloids grouped into the

Eupterodactyloidea Eupterodactyloidea (meaning "true Pterodactyloidea") is an extinct group of pterodactyloid pterosaurs that existed from the latest Late Jurassic to the latest Late Cretaceous periods (Tithonian to Maastrichtian stages). Eupterodactyloids lived on ...

References

{{Taxonbar, from=Q6901581 Callovian first appearances Maastrichtian extinctions