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Besanosaurus
''Besanosaurus'' (meaning ) is an extinct genus of Middle Triassic ichthyosaur from Monte San Giorgio of Italy and Switzerland, containing the single species ''B. leptorhynchus''. ''Besanosaurus'' was named by Cristiano Dal Sasso and Giovanni Pinna in 1996, based on the nearly complete flattened skeleton BES SC 999, the holotype specimen. This skeleton is preserved across multiple thin rock slabs spanning when assembled and took thousands of hours to Fossil preparation, prepare. Additional specimens from Monte San Giorgio that have previously been considered separate genera, including a partial skull named ''Mikadocephalus'' and a well-preserved, largely complete skeleton, have been reinterpreted as additional specimens of ''Besanosaurus''. Putative specimens of ''Besanosaurus'' have been discovered in the Norway, Norwegian archipelago of Svalbard and Germany, although their attribution to this genus remains disputed. As an ichthyosaur, ''Besanosaurus'' had Flipper (anatomy), fli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shastasaurid
Shastasauridae is an extinct family of ichthyosaurs from the Late Triassic with a possible Early Jurassic record. The family contains the largest known species of ichthyosaurs, which include some of and possibly the largest known marine reptiles. Taxonomy Shastasauridae was named by American paleontologist John Campbell Merriam in 1895 along with the newly described genus ''Shastasaurus''. In 1999, Ryosuke Motani erected the clade Shastasauria to include '' Shastasaurus'', ''Shonisaurus'', and several other traditional shastasaurids, defining it as a stem-based taxon including "all merriamosaurians more closely related to '' Shastasaurus pacificus'' than to ''Ichthyosaurus communis''." He also redefined Shastasauridae as a node-based taxon including "the last common ancestor of ''Shastasaurus pacificus'' and '' Besanosaurus leptorhynchus'', and all its descendants" and Shastasaurinae, which Merriam named in 1908, as a stem taxon including "the last common ancestor of ''Shastasau ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ichthyosaur
Ichthyosauria is an order of large extinct marine reptiles sometimes referred to as "ichthyosaurs", although the term is also used for wider clades in which the order resides. Ichthyosaurians thrived during much of the Mesozoic era; based on fossil evidence, they first appeared around 250 million years ago ( Ma) and at least one species survived until about 90 million years ago, into the Late Cretaceous. During the Early Triassic epoch, ichthyosaurs and other ichthyosauromorphs evolved from a group of unidentified land reptiles that returned to the sea, in a development similar to how the mammalian land-dwelling ancestors of modern-day dolphins and whales returned to the sea millions of years later, which they gradually came to resemble in a case of convergent evolution. Ichthyosaurians were particularly abundant in the Late Triassic and Early Jurassic periods, until they were replaced as the top aquatic predators by another marine reptilian group, the Plesiosauria, i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cristiano Dal Sasso
Cristiano Dal Sasso (born 12 September 1965) is an Italian paleontologist. He is known for having participated in the description of notable sauropsids such as the ichthyosaur ''Besanosaurus'' and the theropod dinosaurs ''Scipionyx'' and ''Saltriovenator''. Biography He was born in Monza, Italy and has been working since 1991 for the Milan Natural History Museum where he is the curator of fossil reptiles and birds. He was the technical coordinator of the excavations of Besano, which brought to light the complete skeleton of a Middle Triassic marine reptile of the order of Ichthyosauria, the ''Besanosaurus'' with embryos in the belly, published in 1996 along with Giovanni Pinna. He studied ''Scipionyx'', the first dinosaur found in Italy at Pietraroja, whose description appeared in ''Nature'' in 1998. This small theropod dinosaur, nicknamed "Ciro", generated much publicity because of the unique preservation of large areas of petrified soft tissue and internal organs such as m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Besano
Besano is a town and ''comune'' located in the province of Varese, in the Lombardy region of northern Italy. Paleontological site The fossils of Besano In 1993 the fossil of a Triassic aquatic reptile dating back to about 235 million years was found near the town. It was named ''Besanosaurus''. Many other fossils have emerged from the fossiliferous A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved i ... field of Besano-Monte San Giorgio, known and appreciated since the mid-nineteenth century. References Cities and towns in Lombardy {{Varese-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caudal Fin
Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish swim. Apart from the tail or caudal fin, fish fins have no direct connection with the back bone and are supported only by muscles. Fish fins are distinctive anatomical features with varying structures among different clades: in ray-finned fish (Actinopterygii), fins are mainly composed of bony spines or rays covered by a thin stretch of scaleless skin; in lobe-finned fish (Sarcopterygii) such as coelacanths and lungfish, fins are short rays based around a muscular central bud supported by jointed bones; in cartilaginous fish (Chondrichthyes) and jawless fish (Agnatha), fins are fleshy " flippers" supported by a cartilaginous skeleton. Fins at different locations of the fish body serve different purposes, and are divided into two groups: the midsagittal ''unpaired fins'' and the more laterally located ''paired fins''. Unpaired fins are predominan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thecodont Dentition
Thecodont dentition is a morphological arrangement in which the base of the tooth is completely enclosed in a deep socket of bone, as seen in crocodilians, dinosaurs and mammals, and opposed to acrodont and pleurodont dentition seen in squamate reptiles. Notably, this appears to be the ancestral tooth condition in Amniota Amniotes are tetrapod vertebrate animals belonging to the clade Amniota, a large group that comprises the vast majority of living terrestrial and semiaquatic vertebrates. Amniotes evolved from amphibious stem tetrapod ancestors during the C .... This morphology was once used as a basis for the now-defunct taxonomic group Thecodontia. References Dentition types Archosaurs {{Vertebrate anatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coronoid Process Of The Mandible
In human anatomy, the mandible's coronoid process () is a thin, triangular eminence, which is flattened from side to side and varies in shape and size. Its anterior border is convex and is continuous below with the anterior border of the ramus. Its ''posterior border'' is concave and forms the anterior boundary of the mandibular notch. The ''lateral surface'' is smooth, and affords insertion to the temporalis and masseter muscles. Its ''medial surface'' gives insertion to the temporalis, and presents a ridge which begins near the apex of the process and runs downward and forward to the inner side of the last molar tooth. Between this ridge and the anterior border is a grooved triangular area, the upper part of which gives attachment to the temporalis, the lower part to some fibers of the buccinator. Clinical significance Fractures of the mandible are common. However, coronoid process fractures are very rare. Isolated fractures of the coronoid process caused by direct trauma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vertebrae
Each vertebra (: vertebrae) is an irregular bone with a complex structure composed of bone and some hyaline cartilage, that make up the vertebral column or spine, of vertebrates. The proportions of the vertebrae differ according to their spinal segment and the particular species. The basic configuration of a vertebra varies; the vertebral body (also ''centrum'') is of bone and bears the load of the vertebral column. The upper and lower surfaces of the vertebra body give attachment to the intervertebral discs. The posterior part of a vertebra forms a vertebral arch, in eleven parts, consisting of two pedicles (pedicle of vertebral arch), two laminae, and seven process (anatomy), processes. The laminae give attachment to the ligamenta flava (ligaments of the spine). There are vertebral notches formed from the shape of the pedicles, which form the intervertebral foramina when the vertebrae articulation (anatomy), articulate. These foramina are the entry and exit conduits for the spi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Humeri
The humerus (; : humeri) 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 and 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 Late Latin , from Latin , meaning upper arm, shoulder, and is linguistically related to Gothic (shoulder) and Greek . Structure Upper extremity The upper ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Middle Triassic
In the geologic timescale, the Middle Triassic is the second of three epoch (geology), epochs of the Triassic period (geology), period or the middle of three series (stratigraphy), series in which the Triassic system (stratigraphy), system is divided in chronostratigraphy. The Middle Triassic spans the time between annum, Ma and Ma (million years ago). It is preceded by the Early Triassic Epoch and followed by the Late Triassic Epoch. The Middle Triassic is divided into the Anisian and Ladinian age (geology), ages or stage (stratigraphy), stages. Formerly the middle series in the Triassic was also known as Muschelkalk. This name is now only used for a specific unit of stratum, rock strata with approximately Middle Triassic age, found in western Europe. Middle Triassic life Following the Permian–Triassic extinction event, the most devastating of all mass-extinctions, life recovered slowly. In the Middle Triassic, many groups of organisms reached higher diversity again, s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phalanges
The phalanges (: phalanx ) are digit (anatomy), digital bones in the hands and foot, feet of most vertebrates. In primates, the Thumb, thumbs and Hallux, big toes have two phalanges while the other Digit (anatomy), 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 hallux, big 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 Anatomical terms of locatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Germany
Germany, officially the Federal Republic of Germany, is a country in Central Europe. It lies between the Baltic Sea and the North Sea to the north and the Alps to the south. Its sixteen States of Germany, constituent states have a total population of over 84 million in an area of , making it the most populous member state of the European Union. It borders Denmark to the north, Poland and the Czech Republic to the east, Austria and Switzerland to the south, and France, Luxembourg, Belgium, and the Netherlands to the west. The Capital of Germany, nation's capital and List of cities in Germany by population, most populous city is Berlin and its main financial centre is Frankfurt; the largest urban area is the Ruhr. Settlement in the territory of modern Germany began in the Lower Paleolithic, with various tribes inhabiting it from the Neolithic onward, chiefly the Celts. Various Germanic peoples, Germanic tribes have inhabited the northern parts of modern Germany since classical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
