The Rhamphorhynchoidea forms one of the two
suborder
Order ( la, ordo) is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between family and class. In biological classification, the order is a taxonomic rank used in the classification of organisms and ...
s of
pterosaur
Pterosaurs (; from Greek ''pteron'' and ''sauros'', meaning "wing lizard") is an extinct clade of flying reptiles in the Order (biology), order, Pterosauria. They existed during most of the Mesozoic: from the Late Triassic to the end of the Cre ...
s and represents an
evolutionary grade
A grade is a taxon united by a level of morphological or physiological complexity. The term was coined by British biologist Julian Huxley, to contrast with clade, a strictly phylogenetic unit.
Definition
An evolutionary grade is a group of s ...
of primitive members of flying
reptiles. This suborder is
paraphyletic
In taxonomy (general), taxonomy, a group is paraphyletic if it consists of the group's most recent common ancestor, last common ancestor and most of its descendants, excluding a few Monophyly, monophyletic subgroups. The group is said to be pa ...
unlike the
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 ...
, which arose from within the Rhamphorhynchoidea as opposed to a more distant common ancestor. Because it is not a completely natural grouping, Rhamphorhynchoidea is not used as a formal group in most scientific literature, though some pterosaur scientists continue to use it as an informal grouping in popular works, such as ''The Pterosaurs: From Deep Time'' by David Unwin, and in some formal studies.
Rhamphorhynchoids were the first pterosaurs to have appeared, in the late
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 period ...
Period (
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 ...
age, about 210 million years ago
[Butler, R.J., Barrett, P.M., and gower, D.J. (2009). "Postcranial skeletal pneumaticity and air-sacs in the earliest pterosaurs." ''Biology Letters'', 5(4): 557–560. ]). Unlike their descendants, the pterodactyloids, most rhamphorhynchoids had teeth and long tails, and most species lacked a bony crest, though several are known to have crests formed from soft tissue like
keratin
Keratin () is one of a family of structural fibrous proteins also known as ''scleroproteins''. Alpha-keratin (α-keratin) is a type of keratin found in vertebrates. It is the key structural material making up scales, hair, nails, feathers, ...
. They were generally small, with wingspans rarely exceeding 2.5 meters, though one specimen alluded to by
Alexander Stoyanow would be among the largest pterosaurs of all time with a wingspan of 10 meters, comparable to the largest
azhdarchids.
However, this alleged giant Jurassic pterosaur specimen is not recorded anywhere outside the original ''
Time
Time is the continued sequence of existence and events that occurs in an apparently irreversible succession from the past, through the present, into the future. It is a component quantity of various measurements used to sequence events, t ...
'' article. Nearly all rhamphorhynchoids had become extinct by the end of the
Jurassic
The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately Mya. The J ...
Period, though some
anurognathids persisted to the early Cretaceous. The family
Wukongopteridae, which shows a mix of rhamphorhynchoid and pterodactyloid features, is known from the
Daohugou Beds
The Haifanggou Formation (), also known as the Jiulongshan Formation (), is a fossil-bearing rock deposit located near Daohugou () village of Ningcheng County, in Inner Mongolia, northeastern China.
The formation consists of coarse conglomerate ...
which are most commonly dated to the Jurassic, but a few studies give a Cretaceous date. Furthermore, remains of a non-pterodactyloid from the
Candeleros Formation
The Candeleros Formation (formerly known as the Candeleros Member of the "Río Limay Formation") is a geologic formation that crops out in the Río Negro, Neuquén, and Mendoza provinces of northern Patagonia, Argentina. It is the oldest formati ...
extend the presence of basal pterosaurs into at least the early Late Cretaceous.
[Haluza, A. Y Apesteguía, S, Pterosaur remains (Archosauria, Ornithodira) from the early Late Cretaceous of “La Buitrera”, Río Negro, Argentina, Jornada; XXIII Jornadas Argentinas de Paleontología de Vertebrados; 2007]
Classification
Taxonomy
Listing of families and superfamilies within the suborder Rhamphorhynchoidea, after Unwin 2006 unless otherwise noted.
[
* Order Pterosauria
** Suborder Rhamphorhynchoidea *
***Clade Eopterosauria
**** '']Preondactylus
''Preondactylus'' is a genus of long-tailed pterosaurs from the Late Triassic (late Norian)Barrett, P. M., Butler, R. J., Edwards, N. P., & Milner, A. R. (2008). Pterosaur distribution in time and space: an atlas. ''Zitteliana'', 61-107/ref> that ...
''
****Clade Eudimorphodontimorpha
*****'' Austriadactylus''
*****Clade Eudimorphodontia
Eudimorphodontidae is an extinct family of early pterosaurs from the Late Triassic (Late Carnian to Late Rhaetian age) of Europe.Barrett, P. M., Butler, R. J., Edwards, N. P., & Milner, A. R. (2008). Pterosaur distribution in time and space: an ...
******'' Peteinosaurus''
******Family Eudimorphodontidae
*******Subfamily Eudimorphodontinae
********'' Eudimorphodon''
*******Subfamily Raeticodactylinae
********'' Caviramus''
********'' Carniadactylus''?
*** Family Dimorphodontidae
Dimorphodontidae (or dimorphodontids) is a group of early " rhamphorhynchoid" pterosaurs named after ''Dimorphodon'', that lived in the Late Triassic to Early Jurassic. While fossils that can be definitively referred to the group are rare, dim ...
*** Family Anurognathidae
*** Superfamily Campylognathoidea
Novialoidea (meaning "new wings") is an extinct clade of macronychopteran pterosaurs that lived from the latest Early Jurassic to the latest Late Cretaceous (early Toarcian to late Maastrichtian ageBarrett, P. M., Butler, R. J., Edwards, N. P., ...
**** Family Campylognathoididae
Novialoidea (meaning "new wings") is an extinct clade of macronychopteran pterosaurs that lived from the latest Early Jurassic to the latest Late Cretaceous (early Toarcian to late Maastrichtian ageBarrett, P. M., Butler, R. J., Edwards, N. P., ...
*** Family Rhamphorhynchidae
**** Subfamily Rhamphorhynchinae
**** Subfamily Scaphognathinae
* Rhamphorhynchoids of uncertain relationships (''incertae sedis
' () or ''problematica'' is a term used for a taxonomic group where its broader relationships are unknown or undefined. Alternatively, such groups are frequently referred to as "enigmatic taxa". In the system of open nomenclature, uncertain ...
'')
** '' Comodactylus''
** ''Laopteryx
''Laopteryx'' is the name assigned to a pterosaur (flying reptile) from the Upper Jurassic Morrison Formation of Wyoming, United States; it was originally thought to be a bird.
The genus was named in 1881 by Othniel Charles Marsh. The generic n ...
''
** '' Parapsicephalus''
** '' Rhamphinion''
References
* Unwin, D. M., (2003). "On the phylogeny and evolutionary history of pterosaurs." In Buffetaut, E. & Mazin, J.-M., eds. ''Evolution and Palaeobiology of Pterosaurs''. London: Geological Society of London, Special Publications 217, 2003, pp. 139–190.
{{Taxonbar, from=Q1779482
Pterosaurs
Paraphyletic groups