Grabauornis Temporal range: Aptian ~ | |
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Scientific classification ![]() | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Clade: | Dinosauria |
Clade: | Saurischia |
Clade: | Theropoda |
Clade: | Avialae |
Clade: | † Enantiornithes |
Clade: | † Euenantiornithes |
Genus: | † Grabauornis Dalsätt et al., 2014 |
Species: | †G. lingyuanensis |
Binomial name | |
†Grabauornis lingyuanensis Dalsätt et al., 2014 | |
Grabauornis is an extinct genus of enantiornitheans from the Early Cretaceous of China. [1] [2]
The type species, Grabauornis lingyuanensis, was named and described in 2014 by Johan Dalsätt, Per Ericson and Zhou Zhonghe. The genus name combines a reference to Amadeus William Grabau with the Greek word ὄρνις, which means bird. The specific name refers to the place where it was found; the city of Lingyuan in the Lianoning province of China. Dalsät already referred to the descriptive article in 2012, before it was published, in his dissertation and the name Grabauornis was mentioned with it. However it was still an invalid nomen ex dissertatione. In addition, he explicitly stated that he did not want to perform naming acts, if they are not performed validly.
The fossil, holotype IVPP V14595, was found in a layer of the Yixian Formation which dates to the Aptian, at an age of 125 million years. The holotype consists of a well-preserved skeleton, compressed onto a single plate.
Grabauornis shows a unique combination of differentiating traits. The center of the back of the sternum plate extends further back than the side wings, the latter are fan-shaped. It also has a relatively short head with small, conical teeth. As for the arms and hands; the second and third phalanges of the second finger are quite robust, the third metacarpal extends further than the second and the hand is shorter than the ulna. Besides that, the shoulder blade is long and narrow and tapers towards the top. [3]
Grabauornis has a humerus that is 95% of the length of the ulna. In most enantiornitheans the values are between 77 and 125%, so Grabauornis has an average ratio. According to the descriptors, this indicates a good ability to fly; only above 130% the animal would have to remain on the ground. This ability would be confirmed by the possession of an alula, a thumb feather that could serve as a nose vane. The hypocleidium of the wishbone is also well developed. [3]
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 eighty 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.
Longipteryx is a genus of prehistoric bird which lived during the Early Cretaceous. 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 and some isolated bones are known to date.
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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.
Cathayornis is a genus of enantiornithean birds from the Jiufotang Formation of Liaoning, People's Republic of China. It is known definitively from only one species, Cathayornis yandica, one of the first Enantiornithes found in China. Several additional species were once incorrectly classified as Cathayornis, and have since been reclassified or regarded as nomina dubia.
Dapingfangornis was an enantiornithean bird. It lived during the Early Cretaceous and is known from fossils—including a complete skeleton—found in the Jiufotang Formation in Liaoning province, People's Republic of China. Small to medium-sized, it had a sternum with both long and short lateral processes, and a unique thorn-like process on its nares.
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.
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.
Ningchengopterus is a genus of pterodactyloid pterosaur from the Early Cretaceous period. Its fossil remains were found in the Yixian Formation of what is now China.
Baotianmansaurus is a genus of titanosaur sauropod dinosaur. Its fossils have been found in Upper Cretaceous rocks in Henan, China, within the Gaogou Formation. The type species is B. henanensis, described in 2009. The holotype is 41H III-0200. Remains of the fossils were vertebrae, ribs and scapula fragments. It was probably a close relative of Opisthocoelicaudia and Dongyangosaurus in Saltasauridae.
The Xinlong Formation is an Early Cretaceous geologic formation in Guangxi, southern China.
Shenqiornis is a genus of enantiornithean dinosaurs. It was found in the Qiaotou Member of the Huajiying Formation of Hebei Province, China, and is therefore of uncertain age. The Qiaotou Member may correlate with the more well-known Early Cretaceous Yixian Formation, and so probably is dated to the Aptian, around 122 million years ago.
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.
Shengjingornis is a genus of enantiornithean bird known from the Early Cretaceous of Jinzhou, western Liaoning, China. Its remains were discovered in Jiufotang Formation deposits, dated to 120 million years ago.
Bohaiornithidae is a group of early predatory enantiornithean dinosaurs from the early Cretaceous Period of China. All known specimens come from the Jiufotang Formation and Yixian Formation, dating to the early Aptian age, 125–120 million years ago. Bohaiornithidae was first coined by Wang and colleagues in 2014. They defined it as the natural group formed by all descendants of the common ancestor of the type species, Bohaiornis guoi, and Shenqiornis mengi.
Crichtonpelta is a genus of extinct herbivorous ankylosaurid dinosaur from the Late Cretaceous (Cenomanian) of China.
Luopterus is an extinct genus of anurognathid pterosaur containing only the holotype species L. mutoudengensis that is known from the Middle Jurassic Tiaojishan Formation of Qinglong, northern Hebei Province, China. It was originally named as a species of Dendrorhynchoides in 2012 but it was moved to the genus Luopterus in 2020. Luopterus was originally thought to be from the Early Cretaceous, with a wingspan that is about 40 centimeters (16 in), making it one of the smallest known pterosaurs.