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Gegepterus Changi
''Gegepterus'' is a genus of ctenochasmatid pterosaur from the Early Cretaceous period of what is now the Yixian Formation of Liaoning, China. Only one species is known, ''G. changi''. History and etymology The genus was named in 2007 by Wang Xiaolin, Alexander Kellner, Zhou Zhonge and Diogenes de Almeida Campos. The type species is ''Gegepterus changi''. The generic name is derived from Manchu ''ge ge'', the title of a princess, in reference to the dainty gracility of the specimen, and a Latinized Greek ''pteron'', "wing". The specific name honors female paleontologist Chang Meemann, who over the years established a cordial relationship between the Chinese and Brazilian authors. In 2008 Wang emended the epithet to ''changae'', but such changes are no longer allowed by the ICZN. It is known from two specimens. The first is holotype IVPP V 11981, which was in 2001 found in grey shales from the lower part of the formation (estimated at 125 million years old), near the cit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early Cretaceous
The Early Cretaceous ( geochronological name) or the Lower Cretaceous (chronostratigraphic name), is the earlier or lower of the two major divisions of the Cretaceous. It is usually considered to stretch from 145 Ma to 100.5 Ma. Geology Proposals for the exact age of the Barremian-Aptian boundary ranged from 126 to 117 Ma until recently (as of 2019), but based on drillholes in Svalbard the defining early Aptian Oceanic Anoxic Event 1a (OAE1a) was carbon isotope dated to 123.1±0.3 Ma, limiting the possible range for the boundary to c. 122–121 Ma. There is a possible link between this anoxic event and a series of Early Cretaceous large igneous provinces (LIP). The Ontong Java-Manihiki-Hikurangi large igneous province, emplaced in the South Pacific at c. 120 Ma, is by far the largest LIP in Earth's history. The Ontong Java Plateau today covers an area of 1,860,000 km2. In the Indian Ocean another LIP began to form at c. 120 Ma, the Kerguelen P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shale
Shale is a fine-grained, clastic sedimentary rock formed from mud that is a mix of flakes of clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4) and tiny fragments (silt-sized particles) of other minerals, especially quartz and calcite.Blatt, Harvey and Robert J. Tracy (1996) ''Petrology: Igneous, Sedimentary and Metamorphic'', 2nd ed., Freeman, pp. 281–292 Shale is characterized by its tendency to split into thin layers ( laminae) less than one centimeter in thickness. This property is called '' fissility''. Shale is the most common sedimentary rock. The term ''shale'' is sometimes applied more broadly, as essentially a synonym for mudrock, rather than in the more narrow sense of clay-rich fissile mudrock. Texture Shale typically exhibits varying degrees of fissility. Because of the parallel orientation of clay mineral flakes in shale, it breaks into thin layers, often splintery and usually parallel to the otherwise indistinguishable beddin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elanodactylus Prolatus
''Elanodactylus'' (meaning "Kite finger") is a genus of ctenochasmatid pterodactyloid pterosaur from the Early Cretaceous period (early Aptian stage) of what is now the Yixian Formation of Liaoning, China. The genus was named in 2008 by Brian Andres and Ji Qiang. The type species is ''Elanodactylus prolatus''. The generic name is derived from the Kite genus ''Elanus'', in reference to the long wings, and Greek ''daktylos'', "finger", referring to the wing finger of pterosaurs. The specific name means "elongated" in Latin, in reference to the elongated middle cervical vertebrae. It is known from a partial postcranial skeleton, holotype NGMC 99-07-1, preserving the wings, sternum, shoulder girdle, ribs, cervical and dorsal vertebrae. It represents an adult individual. In 2010, a second adult was described, specimen LPM-R00078, also a skeleton lacking the skull. The wingspan of the holotype was about , and it is estimated to have weighed . The first phalanx of the wing finger i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kepodactylus Insperatus
''Kepodactylus'' is an extinct genus of ctenochasmatid pterodactyloid pterosaur from the Kimmeridgian-Tithonian-age Upper Jurassic Morrison Formation of Colorado, United States. In 1992, a team from the Denver Museum of Natural History dug up a specimen of the dinosaur ''Stegosaurus stenops'' in Garden Park, Colorado. In the quarry they also found smaller disarticulated bones from other animals, among which were those of a pterosaur new to science. In 1996, Jerald Harris and Kenneth Carpenter named the new genus. The type species is ''Kepodactylus insperatus''. The genus name is derived from Greek, ''kepos'', "garden", a reference to Garden Park and ''daktylos'', "finger", referring to the typical wing finger of pterosaurs. The specific name means "unhoped-for" in Latin, alluding to the fact that the researchers hoped to find a dinosaur, and did not expect a pterosaur. The genus is based on the holotype DMNH 21684, consisting of a cervical vertebra, humerus, several finger b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beipiaopterus
''Beipiaopterus'' is a genus of ctenochasmatid pterosaur from the Early Cretaceous period (Aptian stage) of what is now the Yixian Formation of the China. The genus was named in 2003 by Lü Junchang. The generic name is derived from Beipiao City in Liaoning Province and a Latinized Greek ''pteron'', "wing". The specific epithet honors paleontologist Professor Chen Peiji. The type and only species is based on holotype BPM 0002, a crushed partial skeleton of a subadult individual on a slab, missing the skull. It includes four cervical, fourteen dorsal, three sacral and nine caudal vertebrae, a complete left wing and two hind limbs. Remains of the soft parts have been preserved, including partial wing membranes, a membrane attached to the tibia, a "mane" on the neck and webbing of the feet. It had a wingspan of , and the animal itself had a length of about , however, this is only if the skull had the same length as the remainder of the body: for the neck, ten centimetres for the r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pterodaustrini
Ctenochasmatidae is a group of pterosaurs within the suborder Pterodactyloidea. They are characterized by their distinctive teeth, which are thought to have been used for filter-feeding. Ctenochasmatids lived from the Late Jurassic to the Early Cretaceous periods. The earliest known ctenochasmatid remains date to the Late Jurassic Kimmeridgian age. Previously, a fossil jaw recovered from the Middle Jurassic Stonesfield Slate formation in the United Kingdom, was considered the oldest known. This specimen supposedly represented a member of the family Ctenochasmatidae,Buffetaut, E. and Jeffrey, P. (2012). "A ctenochasmatid pterosaur from the Stonesfield Slate (Bathonian, Middle Jurassic) of Oxfordshire, England." ''Geological Magazine'', (advance online publication) though further examination suggested it actually belonged to a teleosaurid stem-crocodilian instead of a pterosaur. Classification Below is cladogram A cladogram (from Greek ''clados'' "branch" and ''gramma'' "char ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cladogram
A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to descendants, nor does it show how much they have changed, so many differing evolutionary trees can be consistent with the same cladogram. A cladogram uses lines that branch off in different directions ending at a clade, a group of organisms with a last common ancestor. There are many shapes of cladograms but they all have lines that branch off from other lines. The lines can be traced back to where they branch off. These branching off points represent a hypothetical ancestor (not an actual entity) which can be inferred to exhibit the traits shared among the terminal taxa above it. This hypothetical ancestor might then provide clues about the order of evolution of various features, adaptation, and other evolutionary narratives about ance ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Teeth
A tooth ( : teeth) is a hard, calcified structure found in the jaws (or mouths) of many vertebrates and used to break down food. Some animals, particularly carnivores and omnivores, also use teeth to help with capturing or wounding prey, tearing food, for defensive purposes, to intimidate other animals often including their own, or to carry prey or their young. The roots of teeth are covered by gums. Teeth are not made of bone, but rather of multiple tissues of varying density and hardness that originate from the embryonic germ layer, the ectoderm. The general structure of teeth is similar across the vertebrates, although there is considerable variation in their form and position. The teeth of mammals have deep roots, and this pattern is also found in some fish, and in crocodilians. In most teleost fish, however, the teeth are attached to the outer surface of the bone, while in lizards they are attached to the inner surface of the jaw by one side. In cartilaginous fish, s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beak
The beak, bill, or rostrum is an external anatomical structure found mostly in birds, but also in turtles, non-avian dinosaurs and a few mammals. A beak is used for eating, preening, manipulating objects, killing prey, fighting, probing for food, courtship, and feeding young. The terms ''beak'' and ''rostrum'' are also used to refer to a similar mouth part in some ornithischians, pterosaurs, cetaceans, dicynodonts, anuran tadpoles, monotremes (i.e. echidnas and platypuses, which have a beak-like structure), sirens, pufferfish, billfishes and cephalopods. Although beaks vary significantly in size, shape, color and texture, they share a similar underlying structure. Two bony projections – the upper and lower mandibles – are covered with a thin keratinized layer of epidermis known as the rhamphotheca. In most species, two holes called ''nares'' lead to the respiratory system. Etymology Although the word "beak" was, in the past, generally restricted to the sharpened bills o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shoulder Girdle
The shoulder girdle or pectoral girdle is the set of bones in the appendicular skeleton which connects to the arm on each side. In humans it consists of the clavicle and scapula; in those species with three bones in the shoulder, it consists of the clavicle, scapula, and coracoid. Some mammalian species (such as the dog and the horse) have only the scapula. The pectoral girdles are to the upper limbs as the pelvic girdle is to the lower limbs; the girdles are the parts of the appendicular skeleton that anchor the appendages to the axial skeleton. In humans, the only true anatomical joints between the shoulder girdle and the axial skeleton are the sternoclavicular joints on each side. No anatomical joint exists between each scapula and the rib cage; instead the muscular connection or physiological joint between the two permits great mobility of the shoulder girdle compared to the compact pelvic girdle; because the upper limb is not usually involved in weight bearing, its stabilit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gastralium
Gastralia (singular gastralium) are dermal bones found in the ventral body wall of modern crocodilians and tuatara, and many prehistoric tetrapods. They are found between the sternum and pelvis, and do not articulate with the vertebrae. In these reptiles, gastralia provide support for the abdomen and attachment sites for abdominal muscles. The possession of gastralia may be ancestral for Tetrapoda and were possibly derived from the ventral scales found in animals like rhipidistians, labyrinthodonts, and '' Acanthostega'', and may be related to ventral elements of turtle plastrons. Similar, but not homologous cartilagenous elements, are found in the ventral body walls of lizards and anurans. These structures have been referred to as inscriptional ribs, based on their alleged association with the inscriptiones tendinae (the tendons that form the six pack in humans). However, the terminology for these gastral-like structures remains confused. Both types, along with ster ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vertebra
The spinal column, a defining synapomorphy shared by nearly all vertebrates,Hagfish are believed to have secondarily lost their spinal column is a moderately flexible series of vertebrae (singular vertebra), each constituting a characteristic irregular bone whose complex structure is composed primarily of bone, and secondarily of hyaline cartilage. They show variation in the proportion contributed by these two tissue types; such variations correlate on one hand with the cerebral/caudal rank (i.e., location within the backbone), and on the other with phylogenetic differences among the vertebrate taxa. The basic configuration of a vertebra varies, but the bone is its ''body'', with the central part of the body constituting the ''centrum''. The upper (closer to) and lower (further from), respectively, the cranium and its central nervous system surfaces of the vertebra body support attachment to the intervertebral discs. The posterior part of a vertebra forms a vertebral arch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
