Longipteryx Temporal range: Early Cretaceous, | |
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Fossil specimen, Beijing Museum of Natural History | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Clade: | Dinosauria |
Clade: | Saurischia |
Clade: | Theropoda |
Clade: | Avialae |
Clade: | † Enantiornithes |
Family: | † Longipterygidae |
Genus: | † Longipteryx Zhang et al., 2001 |
Species: | †L. chaoyangensis |
Binomial name | |
†Longipteryx chaoyangensis Zhang et al., 2001 | |
Synonyms | |
Camptodontornis yangi? (Li et al., 2010) [1] |
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, China. Apart from the holotype IVPP V 12325 - a fine and nearly complete skeleton — another entire skeleton (IPPV V 12552), some isolated bones (a humerus and furcula, specimens IPPV V 12553, and an ulna, IPPV V 12554) and many other specimens are known to date. [2] [3]
The name Longipteryx means "one with long feathers", from Latin longus, "long" + Ancient Greek pteryx (πτέρυξ), "wing", "feather" or "pinion". The specific name chaoyangensis is from the Latin for "from Chaoyang".
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. 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. [2] [4]
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. [2] The end of the tail is destroyed in the holotype; [2] no rectrices are preserved and while the pygostyle is complete in other skeletons, only halos of short feathers are preserved. [5] 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. [5]
Longipteryx was frugivorous, indicated by the discovery of complete gymnosperm seeds and a lack of gastroliths within two specimens, STM8–86 and STM8–112. [3] Initially, it was interpreted as a piscivore or an insectivore. [2] [6] [7] The authors of the 2024 study who reported direct evidence of frugivory in Longipteryx suggested that researchers should be cautious when predicting the diets in extinct taxa based on "untested morphological proxies". [3]
The affiliations of Longipteryx are not resolved. While it has been sometimes included in the Enantiornithes [2] [8] and groups specifically with Euenantiornithes in some cladistic analyses, [9] [ self-published source? ] it might be basal to or in Enantiornithes, being somewhat reminiscent of the equally puzzling Protopteryx . [10] [ self-published source? ] Its plesiomorphies are comprehensive, as can be expected from its old age, but the autapomorphies appear quite "modern", especially compared to other early Enantiornithes. [2]
A distinct order (Longipterygiformes) and family (Longipterygidae) has been proposed for it. [2] 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. [9] 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.
Confuciusornis is a genus of basal crow-sized avialan from the Early Cretaceous Period of the Yixian and Jiufotang Formations of China, dating from 125 to 120 million years ago. Like modern birds, Confuciusornis had a toothless beak, but closer and later relatives of modern birds such as Hesperornis and Ichthyornis were toothed, indicating that the loss of teeth occurred convergently in Confuciusornis and living birds. It was thought to be the oldest known bird to have a beak, though this title now belongs to an earlier relative Eoconfuciusornis. It was named after the Chinese moral philosopher Confucius. Confuciusornis is one of the most abundant vertebrates found in the Yixian Formation, and several hundred complete specimens have been found.
The Enantiornithes, also known as enantiornithines or enantiornitheans in literature, are a group of extinct avialans, the most abundant and diverse group known from the Mesozoic era. Almost all retained teeth and clawed fingers on each wing, but otherwise looked much like modern birds externally. Over seventy species of Enantiornithes have been named, but some names represent only single bones, so it is likely that not all are valid. The Enantiornithes became extinct at the Cretaceous–Paleogene boundary, along with Hesperornithes and all other non-avian dinosaurs.
Yanornis is an extinct genus of fish-eating Early Cretaceous birds. Two species have been described, both from Liaoning province, China: Yanornis martini, based on several fossils found in the 120-million-year-old Jiufotang Formation at Chaoyang, and Yanornis guozhangi, from the 124-million-year-old Yixian Formation.
Sapeornis is a monotypic genus of avialan dinosaurs which lived during the early Cretaceous period. Sapeornis contains only one species, Sapeornis chaoyangensis.
Eoalulavis is a monotypic genus of enantiornithean bird that lived during the Barremian, in the Lower Cretaceous around 125 million years ago. The only known species is Eoalulavis hoyasi.
Sinornis is a genus of enantiornithean birds from the Lower Cretaceous Jiufotang Formation of the People's Republic of China.
Boluochia zhengi was an enantiornithine bird. It lived during the Early Cretaceous in the time span 121.6-110.6 mya and is known from fossils found in the Jiufotang Formation of Liaoning province, People's Republic of China. Boluochia was first described by Zhou in 1995. A re-analysis of the specimen by Jingmai O'Connor and colleagues found that it was closely related to Longipteryx and could be assigned to the family Longipterygidae.
Eoenantiornis is a genus of enantiornithean birds which lived during the early Cretaceous period. It is known from a single fossil specimen found in the Yixian Formation in Liaoning province, China.
Liaoxiornis is a dubious genus of enantiornithine bird. The only named species is Liaoxiornis delicatus, described by Hou and Chen in 1999. Because the species was named for a hatchling specimen, it cannot be matched with adult specimens, and so it is impossible to determine which, if any, birds from the same rocks represent adults of this species. Luis Chiappe and colleagues therefore regarded it as a nomen vanum or at least a nomen dubium, and recommended that use of the name be abandoned.
Yixianornis is a bird genus from the early Cretaceous period. Its remains have been found in the Jiufotang Formation at Chaoyang dated to the early Aptian age, around 120 million years ago. Only one species, Yixianornis grabaui, is known at present. The specific name, grabaui, is named after American paleontologist Amadeus William Grabau, who surveyed China in the early 20th century.
Paraprotopteryx is a genus of enantiornithean birds from the Mesozoic of China.
Protopteryx is an extinct bird and possibly the basalmost enantiornithean, from the Cretaceous period. The type species is P. fengningensis. It was first discovered in the Sichakou Member of the Yixian Formation or Huajiying Formation of Hebei Province, northern China, dating from 131 Ma ago. Protopteryx has been found in the Daibeigou formation, as well. The name Protopteryx means "primitive feather": "proto-" meaning "the first of" and "-pteryx" meaning "feather" or "wing." The name comes from the fact that Protopteryx feathers are more primitive than those of modern birds, such as the two elongated tail feathers that lack barbs and rami.
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 Natural History Museum, and has accession number DNHM D1878/1 and DNHM1878/2. It was collected from the Lower Cretaceous Dawangzhengzi Beds, middle Yixian Formation, from Lingyuan in the Liaoning Province, China.
Longipterygidae is a family of early enantiornithean avialans from the Early Cretaceous epoch of China. All known specimens come from the Jiufotang Formation and Yixian Formation, dating to the early Aptian age, 125-120 million years ago.
Bohaiornis is a genus of enantiornithean dinosaurs. Fossils have been found from the Lower Cretaceous Jiufotang Formation of western Liaoning, China. The only known species, Bohaiornis guoi, was named by Dongyu Hu, Li Li, Lianhaim Hou and Xing Xu in 2011 on the basis of a fully articulated and well-preserved skeleton of a sub-adult. This specimen, LPM B00167, preserved two long, ribbon-like feathers attached to the tail rather than a fan of shorter pennaceous feathers. It was similar to the slightly older Eoenantiornis, but much larger in size. Bohaiornis is the type species of Bohaiornithidae, a family of large predatory enantiornitheans from the Early Cretaceous.
Camptodontornis is an extinct genus of enantiornithine bird which existed in what is now Chaoyang in Liaoning Province, China during the early Cretaceous period. It is known from a well-preserved skeleton including a skull found in the Jiufotang Formation of Liaoning Province. Its original generic name was "Camptodontus" ; it was named by Li Li, En-pu Gong, Li-dong Zhang, Ya-jun Yang and Lian-hai Hou in 2010. However, the name had previously been used for a genus of beetle. The type species is "Camptodontus" yangi. Demirjian (2019) coined a replacement generic name Camptodontornis. The status of C. yangi as a distinct species is disputed, with Wang et al. (2015) considering it to be a probable synonym of Longipteryx chaoyangensis.
Parvavis is a genus of enantiornithine bird, known from the upper Cretaceous of China in the Jiangdihe Formation. The type and only species, Parvavis chuxiongensis, was recovered in Luojumei Village, Chuxiong City, Yunnan Province, southern China, and it was the only known Mesozoic bird from south China at the time of its discovery. Based on its bone structure, the holotype was determined to be nearly fully grown at its time of death and would have been smaller than Iberomesornis, the smallest known enantiornithine prior to the description of Parvavis.
Imparavis is an extinct genus of enantiornithine birds from the Early Cretaceous (Aptian-aged) Jiufotang Formation of Liaoning Province, China. The genus contains a single species, I. attenboroughi, known from a well-preserved skeleton.
Piscivorenantiornis is a genus of enantiornithine bird from the Jiufotang Formation of Liaoning, China. It is known from a single species, P. insusitatus.