Longipteryx
Encyclopedia
Longipteryx is a genus
of prehistoric bird
which lived during the Early Cretaceous
(Aptian
stage, 120.3 million years ago). It contains a single species, Longipteryx chaoyangensis. Its remains have been recovered from the Jiufotang Formation
at Chaoyang in Liaoning Province, People's Republic of China
. Apart from the holotype
IVPP V 12325 - a fine and nearly complete skeleton — another entire skeleton (IPPV V 12552) and some isolated bones (a humerus
and furcula
, specimens IPPV V 12553, and an ulna
, IPPV V 12554) are known to date.
The name Longipteryx means "one with long feathers", from Latin
longus, "long" + Ancient Greek
pteryx (πτέρυξ), "wing", "feather" or "pinion". The species name chaoyangensis is from the Latin for "from Chaoyang".
es which strengthened the ribcage. Its claws and toes were long and strong while the leg was quite short. Altogether, the ability to fly and to perch was quite sophisticated for its age, to the detriment of terrestrial
locomotion: the humerus
was 1.56 times the length of the femur
.
The holotype retains many feather impressions, though poorly preserved; remiges do not seem to have been preserved, and what feathers remain are apparently only body feathers, wing coverts and down. Unfortunately, the end of the tail is destroyed in the holotype; no rectrices are preserved and while the pygostyle
is complete in other skeletons, only halos of short feathers are preserved. While the related Shanweiniao
and some other enantiornithines preserve two, four, or eight long display feathers on the tail, the absence of such feathers in any known specimen of Longipteryx probably indicates that they were absent in this species.
Longipteryx probably dived or probed for fish, crustacean
s, or other aquatic animals of appropriate size. Altogether, it was perhaps closest to a modern-day kingfisher
in its ecological niche
.
and groups specifically with Euenantiornithes
in some cladistic analyses, it might be basal to or in Enantiornithes, being somewhat reminiscent of the equally puzzling Protopteryx
. Its plesiomorphies are comprehensive, as can be expected from its old age, but the autapomorphies appear quite "modern", especially compared to other early Enantiornithes.
A distinct order
(Longipterygiformes) and family
(Longipterygidae) has been proposed for it. Given that neither its exact relationships nor any close relatives are presently known, not much can be said about the phylogenetic position of L. chaoyangensis. On the other hand, Longirostravis hani, described a few years after Longipteryx, appears to be phylogenetically closer to the present taxon
than other Mesozoic
birds and indeed they might constitute a clade
of early specialized Euenantiornithes. If this is correct, they might well be considered as an order, in which case Longirostravisiformes and Longirostravisidae would become junior synonyms of Longipterygiformes and Longipterygidae, respectively.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of prehistoric bird
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
which lived during the Early Cretaceous
Cretaceous
The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...
(Aptian
Aptian
The Aptian is an age in the geologic timescale or a stage in the stratigraphic column. It is a subdivision of the Early or Lower Cretaceous epoch or series and encompasses the time from 125.0 ± 1.0 Ma to 112.0 ± 1.0 Ma , approximately...
stage, 120.3 million years ago). It contains a single species, Longipteryx chaoyangensis. Its remains have been recovered from the Jiufotang Formation
Jiufotang Formation
The Jiufotang Formation is an Early Cretaceous geological formation in Chaoyang, Liaoning which has yielded fossils of feathered dinosaurs, primitive birds, pterosaurs, and other organisms. . It is a member of the Jehol group. The exact age of the Jiufotang has been debated for years, with...
at Chaoyang in Liaoning Province, People's Republic of China
People's Republic of China
China , officially the People's Republic of China , is the most populous country in the world, with over 1.3 billion citizens. Located in East Asia, the country covers approximately 9.6 million square kilometres...
. Apart from the holotype
Holotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...
IVPP V 12325 - a fine and nearly complete skeleton — another entire skeleton (IPPV V 12552) and some isolated bones (a humerus
Humerus
The humerus is a long bone in the arm or forelimb that runs from the shoulder to the elbow....
and furcula
Furcula
The ' is a forked bone found in birds, formed by the fusion of the two clavicles. In birds, its function is the strengthening of the thoracic skeleton to withstand the rigors of flight....
, specimens IPPV V 12553, and an ulna
Ulna
The ulna is one of the two long bones in the forearm, the other being the radius. It is prismatic in form and runs parallel to the radius, which is shorter and smaller. In anatomical position The ulna is one of the two long bones in the forearm, the other being the radius. It is prismatic in form...
, IPPV V 12554) are known to date.
The name Longipteryx means "one with long feathers", from Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
longus, "long" + Ancient Greek
Ancient Greek
Ancient Greek is the stage of the Greek language in the periods spanning the times c. 9th–6th centuries BC, , c. 5th–4th centuries BC , and the c. 3rd century BC – 6th century AD of ancient Greece and the ancient world; being predated in the 2nd millennium BC by Mycenaean Greek...
pteryx (πτέρυξ), "wing", "feather" or "pinion". The species name chaoyangensis is from the Latin for "from Chaoyang".
Description
Excluding the tail, Longipteryx was some 15 cm long overall in life. It had a long bill — longer than the rest of the head — with a few hooked teeth at the tip, and, as the name implies, proportionally long and strong wings. Although it was primitive insofar as that it had two long separate fingers with claws and a stubby thumb, the flight apparatus was generally quite well developed, and unlike most other birds of its time it possessed uncinate processUncinate process
Uncinate process can refer to:* Uncinate process of ethmoid bone* Uncinate process of vertebra - a hook shaped process on the lateral borders of the superior surface of the vertebral bodies of the third to the seventh cervical vertebrae....
es which strengthened the ribcage. Its claws and toes were long and strong while the leg was quite short. Altogether, the ability to fly and to perch was quite sophisticated for its age, to the detriment of terrestrial
Terrestrial animal
Terrestrial animals are animals that live predominantly or entirely on land , as compared with aquatic animals, which live predominantly or entirely in the water , or amphibians, which rely on a combination of aquatic and terrestrial habitats...
locomotion: the humerus
Humerus
The humerus is a long bone in the arm or forelimb that runs from the shoulder to the elbow....
was 1.56 times the length of the femur
Femur
The femur , or thigh bone, is the most proximal bone of the leg in tetrapod vertebrates capable of walking or jumping, such as most land mammals, birds, many reptiles such as lizards, and amphibians such as frogs. In vertebrates with four legs such as dogs and horses, the femur is found only in...
.
The holotype retains many feather impressions, though poorly preserved; remiges do not seem to have been preserved, and what feathers remain are apparently only body feathers, wing coverts and down. Unfortunately, the end of the tail is destroyed in the holotype; no rectrices are preserved and while the pygostyle
Pygostyle
Pygostyle refers to a number of the final few caudal vertebrae fused into a single ossification, supporting the tail feathers and musculature. In modern birds, the rectrices attach to these....
is complete in other skeletons, only halos of short feathers are preserved. While the related Shanweiniao
Shanweiniao
Shanweiniao is an extinct genus of long-beaked enantiornithine bird from Early Cretaceous China. One species is known, Shanweiniao cooperorum. There is one known fossil, a slab and counterslab. The fossil is in the collection of the Dalian Natural History Museum, and has accession number DNHM...
and some other enantiornithines preserve two, four, or eight long display feathers on the tail, the absence of such feathers in any known specimen of Longipteryx probably indicates that they were absent in this species.
Longipteryx probably dived or probed for fish, crustacean
Crustacean
Crustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span...
s, or other aquatic animals of appropriate size. Altogether, it was perhaps closest to a modern-day kingfisher
Kingfisher
Kingfishers are a group of small to medium sized brightly coloured birds in the order Coraciiformes. They have a cosmopolitan distribution, with most species being found in the Old World and Australia...
in its ecological niche
Ecological niche
In ecology, a niche is a term describing the relational position of a species or population in its ecosystem to each other; e.g. a dolphin could potentially be in another ecological niche from one that travels in a different pod if the members of these pods utilize significantly different food...
.
Classification
The affiliations of Longipteryx are not resolved. While it has been sometimes included in the EnantiornithesEnantiornithes
Enantiornithes is an extinct group of primitive birds. They were the most abundant and diverse avialans of the Mesozoic. Almost all retained teeth and clawed fingers on each wing, but otherwise looked much like modern birds externally. Over 50 species of Enantiornithines have been named, but some...
and groups specifically with Euenantiornithes
Euenantiornithes
Euenantiornithes is a superorder of Cretaceous birds. They are considered to contain the more advanced taxa of the Enantiornithes, the dominant group of birds during the late Mesozoic...
in some cladistic analyses, it might be basal to or in Enantiornithes, being somewhat reminiscent of the equally puzzling Protopteryx
Protopteryx
Protopteryx is an extinct genus of bird, perhaps an enantiornithine, from the Cretaceous in China. The type species is P. fengningensis...
. Its plesiomorphies are comprehensive, as can be expected from its old age, but the autapomorphies appear quite "modern", especially compared to other early Enantiornithes.
A distinct order
Order (biology)
In scientific classification used in biology, the order is# a taxonomic rank used in the classification of organisms. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, and species, with order fitting in between class and family...
(Longipterygiformes) and family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
(Longipterygidae) has been proposed for it. Given that neither its exact relationships nor any close relatives are presently known, not much can be said about the phylogenetic position of L. chaoyangensis. On the other hand, Longirostravis hani, described a few years after Longipteryx, appears to be phylogenetically closer to the present taxon
Taxon
|thumb|270px|[[African elephants]] form a widely-accepted taxon, the [[genus]] LoxodontaA taxon is a group of organisms, which a taxonomist adjudges to be a unit. Usually a taxon is given a name and a rank, although neither is a requirement...
than other Mesozoic
Mesozoic
The Mesozoic era is an interval of geological time from about 250 million years ago to about 65 million years ago. It is often referred to as the age of reptiles because reptiles, namely dinosaurs, were the dominant terrestrial and marine vertebrates of the time...
birds and indeed they might constitute a 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...
of early specialized Euenantiornithes. If this is correct, they might well be considered as an order, in which case Longirostravisiformes and Longirostravisidae would become junior synonyms of Longipterygiformes and Longipterygidae, respectively.
External links
- L. chaoyangensis at shanghai-fossil.com [in Chinese]. Contains photos of holotype with fossilized plumage. Retrieved 2007-OCT-29