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Dearc
''Dearc'' ( ) is a genus of large-bodied rhamphorhynchine pterosaur from the Middle Jurassic Lealt Shale Formation of Scotland. The holotype, a juvenile or subadult that was still actively growing, has an estimated wingspan of 2.5 to 3 meters, making it the largest flying animal of its time. This pushes the origin of large pterosaurs back significantly, as it was previously assumed that pterosaurs did not reach greater body sizes until the short-tailed pterodactyloid lineages of the Cretaceous. The genus contains a single species, ''Dearc sgiathanach'' ( ). Discovery and naming The holotype of ''Dearc'', NMS G.2021.6.1-4, was found in 2017 by Amelia Penny in the Lealt Shale Formation and consists of a three-dimensionally preserved skeleton preserved in articulation in a slab of limestone (separated into four pieces for preparation). The specimen preserves most of the body with the exception of the end of the tail, most of the hindlimbs, parts of the wing and the very tip of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dearc Wingspan
''Dearc'' ( ) is a genus of large-bodied rhamphorhynchine pterosaur from the Middle Jurassic Lealt Shale Formation of Scotland. The holotype, a juvenile or subadult that was still actively growing, has an estimated wingspan of 2.5 to 3 meters, making it the largest flying animal of its time. This pushes the origin of large pterosaurs back significantly, as it was previously assumed that pterosaurs did not reach greater body sizes until the short-tailed pterodactyloid lineages of the Cretaceous. The genus contains a single species, ''Dearc sgiathanach'' ( ). Discovery and naming The holotype of ''Dearc'', NMS G.2021.6.1-4, was found in 2017 by Amelia Penny in the Lealt Shale Formation and consists of a three-dimensionally preserved skeleton preserved in articulation in a slab of limestone (separated into four pieces for preparation). The specimen preserves most of the body with the exception of the end of the tail, most of the hindlimbs, parts of the wing and the very tip of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhamphorhynchine
Rhamphorhynchidae is a group of early pterosaurs named after '' Rhamphorhynchus'', that lived in the Late Jurassic. The family Rhamphorhynchidae was named in 1870 by Harry Govier Seeley.Seeley, H.G. (1870). "The Orithosauria: An Elementary Study of the Bones of Pterodactyles." Cambridge, 135 p. Members of the group possess no more than 11 pairs of teeth in the rostrum, a deltopectoral crest that is constricted at the base but expanded at the distal end, and a bent phalange on the fifth toe. Rhamphorhynchidae traditionally contains two subfamilies: the Rhamphorhynchinae and the Scaphognathinae. While not recovered as distinct clades by all analyses, there do appear to be traits uniting members of each group. Rhamphorhynchines are more common, were lightly built, and had jaws ending in pointed tips that contained more teeth, which are often procumbent (pointed forward). Scaphognathines are comparatively quite rare, were more robust skeletally, and had shorter wing proportions. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lealt Shale Formation
The Lealt Shale Formation is a Middle Jurassic geologic formation in Scotland. Fossil ornithopod , theropod and stegosaur tracks, a theropod dinosaur tooth and the pterosaur ''Dearc'' have been reported from the formation.Weishampel, et al. (2004). "Dinosaur distribution." Pp. 517-607. The lithology consists of silty fissile mudstones with subordinate thin limestones. See also * List of dinosaur-bearing rock formations This list of dinosaur-bearing rock formations is a list of geologic formations in which dinosaur fossils have been documented. Containing body fossils * List of stratigraphic units with dinosaur body fossils ** List of stratigraphic units with few ... ** List of stratigraphic units with ornithischian tracks *** Ornithopod tracks Footnotes References * Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. 861 pp. . Bathonian Stage {{UK-geologic-formation-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dorygnathus
''Dorygnathus'' ("spear jaw") was a genus of Rhamphorhynchidae, rhamphorhynchid pterosaur that lived in Europe during the Early Jurassic period, when shallow seas flooded much of the continent. It had a short () wingspan, and a relatively small triangular sternum, which is where its flight muscles attached. Its skull was long and its eye sockets were the largest Fenestra (anatomy), opening therein. Large curved fangs that "intermeshed" when the jaws closed featured prominently at the front of the snout while smaller, straighter teeth lined the back. Having two or more morphs of teeth, a condition called heterodonty, is rare in modern reptiles but more common in basal ("primitive") pterosaurs. The heterodont dentition in ''Dorygnathus'' is consistent with a piscivore, piscivorous (fish-eating) diet. The fifth digit on the hindlimbs of ''Dorygnathus'' was unusually long and oriented to the side. Its function is not certain, but the toe may have supported a membrane like those support ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monofenestrata
Monofenestrata is an unranked group of pterosaurs that includes the family Wukongopteridae and the suborder Pterodactyloidea. The clade Monofenestrata was in 2009/2010 defined as the group consisting of ''Pterodactylus'' and all species sharing with ''Pterodactylus'' the synapomorphy of an external nostril confluent with the antorbital fenestra, the major skull opening on the side of the snout. The name is derived from Greek ''monos'', "single", and Latin ''fenestra'', "window". The concept was inspired by the discovery of ''Darwinopterus'', a species combining a pterodactyloid-type skull with a more basal build of the remainder of the body. The Darwinoptera, a primitive subgroup of monofenestratans showing this transitional anatomy, was also named for ''Darwinopterus'' and defined as all descendants of its common ancestor with '' Pterorhynchus''. The earliest known monofenestratan fossils have been found in the Stonesfield Slate formation of the United Kingdom, which dates to t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Histology
Histology, also known as microscopic anatomy or microanatomy, is the branch of biology which studies the microscopic anatomy of biological tissues. Histology is the microscopic counterpart to gross anatomy, which looks at larger structures visible without a microscope. Although one may divide microscopic anatomy into ''organology'', the study of organs, ''histology'', the study of tissues, and ''cytology'', the study of cells, modern usage places all of these topics under the field of histology. In medicine, histopathology is the branch of histology that includes the microscopic identification and study of diseased tissue. In the field of paleontology, the term paleohistology refers to the histology of fossil organisms. Biological tissues Animal tissue classification There are four basic types of animal tissues: muscle tissue, nervous tissue, connective tissue, and epithelial tissue. All animal tissues are considered to be subtypes of these four principal tissue types ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sacral Vertebrae
The sacrum (plural: ''sacra'' or ''sacrums''), in human anatomy, is a large, triangular bone at the base of the spine that forms by the fusing of the sacral vertebrae (S1S5) between ages 18 and 30. The sacrum situates at the upper, back part of the pelvic cavity, between the two wings of the pelvis. It forms joints with four other bones. The two projections at the sides of the sacrum are called the alae (wings), and articulate with the ilium at the L-shaped sacroiliac joints. The upper part of the sacrum connects with the last lumbar vertebra (L5), and its lower part with the coccyx (tailbone) via the sacral and coccygeal cornua. The sacrum has three different surfaces which are shaped to accommodate surrounding pelvic structures. Overall it is concave (curved upon itself). The base of the sacrum, the broadest and uppermost part, is tilted forward as the sacral promontory internally. The central part is curved outward toward the posterior, allowing greater room for the pelv ... [...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] |
Scapula
The scapula (plural scapulae or scapulas), also known as the shoulder blade, is the bone that connects the humerus (upper arm bone) with the clavicle (collar bone). Like their connected bones, the scapulae are paired, with each scapula on either side of the body being roughly a mirror image of the other. The name derives from the Classical Latin word for trowel or small shovel, which it was thought to resemble. In compound terms, the prefix omo- is used for the shoulder blade in medical terminology. This prefix is derived from ὦμος (ōmos), the Ancient Greek word for shoulder, and is cognate with the Latin , which in Latin signifies either the shoulder or the upper arm bone. The scapula forms the back of the shoulder girdle. In humans, it is a flat bone, roughly triangular in shape, placed on a posterolateral aspect of the thoracic cage. Structure The scapula is a thick, flat bone lying on the thoracic wall that provides an attachment for three groups of muscles: intrin ... [...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] |
Premaxilla
The premaxilla (or praemaxilla) is one of a pair of small cranial bones at the very tip of the upper jaw of many animals, usually, but not always, bearing teeth. In humans, they are fused with the maxilla. The "premaxilla" of therian mammal has been usually termed as the incisive bone. Other terms used for this structure include premaxillary bone or ''os premaxillare'', intermaxillary bone or ''os intermaxillare'', and Goethe's bone. Human anatomy In human anatomy, the premaxilla is referred to as the incisive bone (') and is the part of the maxilla which bears the incisor teeth, and encompasses the anterior nasal spine and alar region. In the nasal cavity, the premaxillary element projects higher than the maxillary element behind. The palatal portion of the premaxilla is a bony plate with a generally transverse orientation. The incisive foramen is bound anteriorly and laterally by the premaxilla and posteriorly by the palatine process of the maxilla. It is formed from the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
