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Forfexopterus
''Forfexopterus'' (meaning "scissor wings") is a genus of ctenochasmatid pterosaur from the Early Cretaceous Jiufotang Formation in China. It contains a single species, ''F. jeholensis'', named from a mostly complete skeleton by Shunxing Jiang and colleagues in 2016. A second specimen, consisting of a wing, was described in 2020. While the first specimen is larger, it shows signs of being less mature than the second specimen, indicating that the developmental trajectories of ''Forfexopterus'' were variable. Like other ctenochasmatids, ''Forfexopterus'' had a long, low skull filled with many slender teeth; unlike other members of the group, however, it did not have a spatula-shaped snout tip or crests, and its teeth were more curved. A single characteristic distinguishes ''Forfexopterus'' from all other members of the wider group Archaeopterodactyloidea: of the four phalanx bones in its wing finger, the first was shorter than the second but longer than the third. Discovery and nami ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Forfexopterus Comparison
''Forfexopterus'' (meaning "scissor wings") is a genus of ctenochasmatid pterosaur from the Early Cretaceous Jiufotang Formation in China. It contains a single species, ''F. jeholensis'', named from a mostly complete skeleton by Shunxing Jiang and colleagues in 2016. A second specimen, consisting of a wing, was described in 2020. While the first specimen is larger, it shows signs of being less mature than the second specimen, indicating that the developmental trajectories of ''Forfexopterus'' were variable. Like other ctenochasmatids, ''Forfexopterus'' had a long, low skull filled with many slender teeth; unlike other members of the group, however, it did not have a spatula-shaped snout tip or crests, and its teeth were more curved. A single characteristic distinguishes ''Forfexopterus'' from all other members of the wider group Archaeopterodactyloidea: of the four phalanx bones in its wing finger, the first was shorter than the second but longer than the third. Discovery and nami ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ctenochasmatidae
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'' "cha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 Jehol Biota). It is a member of the Jehol group. The exact age of the Jiufotang has been debated for years, with estimates ranging from the Late Jurassic to the Early Cretaceous. New uranium-lead dates reveal the formation is deposited in the Aptian stage of the Early Cretaceous. Fossils of ''Microraptor'' and ''Jeholornis'' are from the Jiufotang. Fossil content Choristoderans Fish Mammaliamorphs Several mammaliamorph specimens have been found from the Jiufotang, but only two have been formally described and named. Ornithischians Pterosaurs Saurischians A large titanosaur is present in the formation. Enantiornithines Euornithines Misc theropods See also * Yixian Formation * List of dinosaur-bearing rock for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plataleorhynchus
''Plataleorhynchus'' is a genus of ctenochasmatid pterodactyloid pterosaur from the Late Jurassic to Early Cretaceous periods ( Tithonian to Berriasian stages) of what is now the Purbeck Limestone of Dorset, England. History and etymology The genus was named in 1995 by Stafford Howse and Andrew Milner. The type species is ''Plataleorhynchus streptophorodon''. The genus name is derived from ''Platalea'', the spoonbill, and Greek , "snout", in reference to the distinctive form of the front of the skull. The specific name is derived from Greek , "collared", and , "tooth", referring to the tooth form. ''Plataleorhynchus'' is based on holotype NHML R.11957 (earlier BMNH R.11957), an incomplete anterior upper jaw with teeth found in a chalkstone quarry near Langton Matravers. The fossil is present on a plate; its underside is visible. This jaw is notable because it expands to form a circular, spatula-like shape at the front, holding 22 narrow teeth that point sideways. Forty oth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Huanhepterus
''Huanhepterus'' is an extinct genus of ctenochasmatid pterodactyloid pterosaur from the Early Cretaceous period of what is now Qingyang, Gansu, China. History The genus was named by Dong Zhiming in 1982. The type species is ''Huanhepterus quingyangensis''. The genus name refers to the Huang Jian (not the Yellow River or "Huang He", but a smaller tributary of the Jinghe River in Gansu), and combines it with a Latinized Greek ''pteron'', "wing". The specific name refers to Qinyang County. ''Huanhepterus'' is based on the holotype specimen, IVPP V9070, a partial articulated skeleton consisting mostly of impressions of the left half of the body and the beak-end of the skull. The fossil was in May 1978 found in a quarry operated by the Sanshilipu-commune, when an explosion exposed a vertebra. Its force obliterated the right half of the specimen. IVPP V9070 hails from the Early Cretaceous-age Huachihuanhe Formation of the Zhidan Group. Description ''Huanhepterus'' had a long, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gnathosaurus
''Gnathosaurus'' (meaning "jawed lizard") is a genus of ctenochasmatid pterosaur containing two species: ''G. subulatus'', named in 1833 from the Solnhofen Limestone of Germany, and ''G. macrurus'', known from the Purbeck Limestone of the UK. Its fossil remains dated back to the Late Jurassic period. History of discovery Fragments of ''Gnathosaurus'' jaws were first discovered in 1832 in the Solnhofen limestones of southern Germany but were mistaken for a piece of teleosaurid crocodile jaw by Georg zu Münster, who first named the species ''Crocodilus multidens'' in that year. Soon afterwards, Hermann von Meyer classified the same specimen as the new genus and species ''Gnathosaurus subulatus'', a name which came to be universally used shortly thereafter. In the 1860s, scientists such as Albert Oppel compared the ''G. subulatus'' jaw fragment to contemporary pterosaurs such as ''Pterodactylus'' and ''Ctenochasma'', and concluded that it was also probably a "flying reptile" rathe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pteranodon
''Pteranodon'' (); from Ancient Greek (''pteron'', "wing") and (''anodon'', "toothless") is a genus of pterosaur that included some of the largest known flying reptiles, with ''P. longiceps'' having a wingspan of . They lived during the late Cretaceous geological period of North America in present-day Kansas, Nebraska, Wyoming, South Dakota and Alabama. More fossil specimens of ''Pteranodon'' have been found than any other pterosaur, with about 1,200 specimens known to science, many of them well preserved with nearly complete skulls and articulated skeletons. It was an important part of the animal community in the Western Interior Seaway. ''Pteranodon'' was not a dinosaur. By definition, all dinosaurs belong to the group Dinosauria; ''Pteranodon'' belongs to the group Pterosauria. Nonetheless, ''Pteranodon'' is the most famous pterosaur, frequently featured in dinosaur media and strongly associated with dinosaurs by the general public. While not dinosaurs, pterosaurs such as ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sexual Dimorphism
Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most animals and some plants. Differences may include secondary sex characteristics, size, weight, colour, markings, or behavioural or cognitive traits. These differences may be subtle or exaggerated and may be subjected to sexual selection and natural selection. The opposite of dimorphism is ''monomorphism'', which is when both biological sexes are phenotypically indistinguishable from each other. Overview Ornamentation and coloration Common and easily identified types of dimorphism consist of ornamentation and coloration, though not always apparent. A difference in coloration of sexes within a given species is called sexual dichromatism, which is commonly seen in many species of birds and reptiles. Sexual selection leads to the exaggerated dim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phalanx Bone
The phalanges (singular: ''phalanx'' ) are digital bones in the hands and feet of most vertebrates. In primates, the thumbs and big toes have two phalanges while the other digits have three phalanges. The phalanges are classed as long bones. Structure The phalanges are the bones that make up the fingers of the hand and the toes of the foot. There are 56 phalanges in the human body, with fourteen on each hand and foot. Three phalanges are present on each finger and toe, with the exception of the thumb and large toe, which possess only two. The middle and far phalanges of the fifth toes are often fused together (symphalangism). The phalanges of the hand are commonly known as the finger bones. The phalanges of the foot differ from the hand in that they are often shorter and more compressed, especially in the proximal phalanges, those closest to the torso. A phalanx is named according to whether it is proximal, middle, or distal and its associated finger or toe. The proximal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 rounded head, a narrow neck, and two short processes (tubercles, sometimes called tuberosities). The body is cylindrical in its upper portion, and more prismatic below. The lower extremity consists of 2 epicondyles, 2 processes (trochlea & capitulum), and 3 fossae (radial fossa, coronoid fossa, and olecranon fossa). As well as its true anatomical neck, the constriction below the greater and lesser tubercles of the humerus is referred to as its surgical neck due to its tendency to fracture, thus often becoming the focus of surgeons. Etymology The word "humerus" is derived from la, humerus, umerus meaning upper arm, shoulder, and is linguistically related to Gothic ''ams'' shoulder and Greek ''ōmos''. Structure Upper extremity The upper or pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epiphysis
The epiphysis () is the rounded end of a long bone, at its joint with adjacent bone(s). Between the epiphysis and diaphysis (the long midsection of the long bone) lies the metaphysis, including the epiphyseal plate (growth plate). At the joint, the epiphysis is covered with articular cartilage; below that covering is a zone similar to the epiphyseal plate, known as subchondral bone. The epiphysis is filled with red bone marrow, which produces erythrocytes (red blood cells). Structure There are four types of epiphysis: # Pressure epiphysis: The region of the long bone that forms the joint is a pressure epiphysis (e.g. the head of the femur, part of the hip joint complex). Pressure epiphyses assist in transmitting the weight of the human body and are the regions of the bone that are under pressure during movement or locomotion. Another example of a pressure epiphysis is the head of the humerus which is part of the shoulder complex. condyles of femur and tibia also comes under ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coracoid
A coracoid (from Greek κόραξ, ''koraks'', raven) is a paired bone which is part of the shoulder assembly in all vertebrates except therian mammals (marsupials and placentals). In therian mammals (including humans), a coracoid process is present as part of the scapula, but this is not homologous with the coracoid bone of most other vertebrates. In other tetrapods it joins the scapula to the front end of the sternum and has a notch on the dorsal surface which, along with a similar notch on the ventral surface of the scapula, forms the socket in which the proximal end of the humerus (upper arm bone) is located. The acrocoracoid process is an expansion adjacent to this contact surface, to which the shoulderward end of the biceps brachii muscle attaches in these animals. In birds (and generally theropods and related animals), the entire unit is rigid and called scapulocoracoid. This plays a major role in bird flight. In dinosaurs the main bones of the pectoral girdle were the sca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
