''Longipteryx'' is a
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
of prehistoric
bird
Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweigh ...
which lived during the Early
Cretaceous
The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of th ...
(
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 121.4 ± 1.0 Ma to 113.0 ± 1.0 Ma (million years ago), a ...
stage, 120.3 million years ago). It contains a single species, ''Longipteryx chaoyangensis''. Its remains have been recovered from the
Jiufotang Formation
The Jiufotang Formation ( Chinese: 九佛堂组, pinyin: ''jiǔfótáng zǔ'') is an Early Cretaceous geological formation in Chaoyang, Liaoning which has yielded fossils of feathered dinosaurs, primitive birds, pterosaurs, and other organisms (see ...
at
Chaoyang in
Liaoning Province
Liaoning () is a coastal provinces of China, province in Northeast China that is the smallest, southernmost, and most populous province in the region. With its capital at Shenyang, it is located on the northern shore of the Yellow Sea, and i ...
,
China
China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's most populous country, with a population exceeding 1.4 billion, slightly ahead of India. China spans the equivalent of five time zones and ...
. Apart from the
holotype
A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several ...
IVPP V 12325 - a fine and nearly complete skeleton — another entire skeleton (IPPV V 12552) and some isolated bones (a
humerus
The humerus (; ) is a long bone in the arm that runs from the shoulder to the elbow. It connects the scapula and the two bones of the lower arm, the radius and ulna, and consists of three sections. The humeral upper extremity consists of a roun ...
and
furcula
The (Latin for "little fork") or wishbone is a forked bone found in most birds and some species of non-avian dinosaurs, and is formed by the fusion of the two pink
clavicles. In birds, its primary function is in the strengthening of the thoracic ...
, specimens IPPV V 12553, and an
ulna
The ulna (''pl''. ulnae or ulnas) is a long bone found in the forearm that stretches from the elbow to the smallest finger, and when in anatomical position, is found on the medial side of the forearm. That is, the ulna is on the same side of t ...
, IPPV V 12554) are known to date.
The name ''Longipteryx'' means "one with long feathers", from
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 ...
''longus'', "long" +
Ancient Greek
Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic peri ...
''pteryx'' (πτέρυξ), "wing", "feather" or "pinion". The
specific 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 basal to the extent 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 processes which strengthened the
ribcage
The rib cage, as an enclosure that comprises the ribs, vertebral column and sternum in the thorax of most vertebrates, protects vital organs such as the heart, lungs and great vessels.
The sternum, together known as the thoracic cage, is a semi- ...
. 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 refers to things related to land or the planet Earth.
Terrestrial may also refer to:
* Terrestrial animal, an animal that lives on land opposed to living in water, or sometimes an animal that lives on or near the ground, as opposed to ...
locomotion: the
humerus
The humerus (; ) is a long bone in the arm that runs from the shoulder to the elbow. It connects the scapula and the two bones of the lower arm, the radius and ulna, and consists of three sections. The humeral upper extremity consists of a roun ...
was 1.56 times the length of the
femur
The femur (; ), or thigh bone, is the proximal bone of the hindlimb in tetrapod vertebrates. The head of the femur articulates with the acetabulum in the pelvic bone forming the hip joint, while the distal part of the femur articulates with ...
.
The holotype retains many feather impressions, though poorly preserved;
remiges
Flight feathers (''Pennae volatus'') are the long, stiff, asymmetrically shaped, but symmetrically paired pennaceous feathers on the wings or tail of a bird; those on the wings are called remiges (), singular remex (), while those on the tail ...
do not seem to have been preserved, and what feathers remain are apparently only body feathers,
wing covert
A covert feather or tectrix on a bird is one of a set of feathers, called coverts (or ''tectrices''), which, as the name implies, cover other feathers. The coverts help to smooth airflow over the wings and tail. Ear coverts
The ear coverts are sm ...
s and
down.
The end of the tail is destroyed in the holotype;
no
rectrices
Flight feathers (''Pennae volatus'') are the long, stiff, asymmetrically shaped, but symmetrically paired pennaceous feathers on the wings or tail of a bird; those on the wings are called remiges (), singular remex (), while those on the tail ...
are preserved and while the
pygostyle
Pygostyle describes a skeletal condition in which the final few caudal vertebrae are fused into a single ossification, supporting the tail feathers and musculature. In modern birds, the rectrices attach to these. The pygostyle is the main compon ...
is complete in other skeletons, only halos of short feathers are preserved.
[ While the related '']Shanweiniao
''Shanweiniao'' is a genus of long-snouted enantiornithean birds 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 ...
'' 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
Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group ...
s, or other aquatic animals of appropriate size. Altogether, it was perhaps closest to a modern-day kingfisher
Kingfishers are a family, the Alcedinidae, of small to medium-sized, brightly colored birds in the order Coraciiformes. They have a cosmopolitan distribution, with most species found in the tropical regions of Africa, Asia, and Oceania, ...
in its ecological niche
In ecology, a niche is the match of a species to a specific environmental condition.
Three variants of ecological niche are described by
It describes how an organism or population responds to the distribution of resources and competitors (for ...
. A study on Mesozoic avian diets does indeed recover it as a piscivore, but a posterior study notes that it is far too smaller to have been a fish-eater, since even similar sized kingfishers are primarily insectivorous. It instead suggests a semi-raptorial lifestyle, using its talons (similar to those of owl
Owls are birds from the order Strigiformes (), which includes over 200 species of mostly solitary and nocturnal birds of prey typified by an upright stance, a large, broad head, binocular vision, binaural hearing, sharp talons, and feathers a ...
s) to grab large insects.
Classification
The affiliations of ''Longipteryx'' are not resolved. While it has been sometimes included in the Enantiornithes
The Enantiornithes, also known as enantiornithines or enantiornitheans in literature, are a group of extinct avialans ("birds" in the broad sense), the most abundant and diverse group known from the Mesozoic era. Almost all retained teeth and cla ...
and groups specifically with Euenantiornithes
The Enantiornithes, also known as enantiornithines or enantiornitheans in literature, are a group of extinct avialans ("birds" in the broad sense), the most abundant and diverse group known from the Mesozoic era. Almost all retained teeth and cla ...
in some cladistic
Cladistics (; ) is an approach to biological classification in which organisms are categorized in groups (" clades") based on hypotheses of most recent common ancestry. The evidence for hypothesized relationships is typically shared derived char ...
analyses, it might be basal to or in Enantiornithes, being somewhat reminiscent of the equally puzzling ''Protopteryx
''Protopteryx'' is an extinct bird and the most basal enantiornithean, from the Cretaceous period.Zhou, Zhonghe. (2002). "A new and primitive enantiornithine bird from the Early Cretaceous of China." ''Journal of Vertebrate Paleontology'', 22(1): ...
''. Its plesiomorph
In phylogenetics, a plesiomorphy ("near form") and symplesiomorphy are synonyms for an ancestral character shared by all members of a clade, which does not distinguish the clade from other clades.
Plesiomorphy, symplesiomorphy, apomorphy, and ...
ies are comprehensive, as can be expected from its old age, but the autapomorph
In phylogenetics, an autapomorphy is a distinctive feature, known as a derived trait, that is unique to a given taxon. That is, it is found only in one taxon, but not found in any others or outgroup taxa, not even those most closely related to t ...
ies appear quite "modern", especially compared to other early Enantiornithes.
A distinct order (Longipterygiformes) and family
Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...
(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
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 ...
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
In biology, a taxon (back-formation from ''taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular nam ...
than other Mesozoic
The Mesozoic Era ( ), also called the Age of Reptiles, the Age of Conifers, and colloquially as the Age of the Dinosaurs is the second-to-last era of Earth's geological history, lasting from about , comprising the Triassic, Jurassic and Cretaceo ...
birds and indeed they might constitute a 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, ...
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 synonym
The Botanical and Zoological Codes of nomenclature treat the concept of synonymy differently.
* In botanical nomenclature, a synonym is a scientific name that applies to a taxon that (now) goes by a different scientific name. For example, Linna ...
s of Longipterygiformes and Longipterygidae, respectively.
References
Footnotes
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*
External links
*
{{Taxonbar, from=Q1869545
Bird genera
Early Cretaceous birds of Asia
Fossil taxa described in 2001
Jiufotang fauna
Longipterygids