|
Paracryptodires
__NOTOC__ Paracryptodira is an extinct group of reptiles in the clade Testudinata (which contains modern turtles and their extinct relatives), known from the Jurassic to Paleogene of North America and Europe. Initially treated as a suborder sister to Cryptodira,Gaffney (1975) they were then thought to be a very primitive lineage inside the Cryptodira according to the most common use of the latter taxon.Joyce (2007) They are now often regarded as late-diverging stem-turtles, lying outside the clade formed by Cryptodira and Pleurodira. Paracryptodires are divided into three main groups, Compsemydidae, known from the Late Jurassic to Paleocene of North America and Europe, Pleurosternidae, known from the Late Jurassic to Early Cretaceous of North America and Europe, and Baenidae, known from the Early Cretaceous to Eocene of North America. The latter two groups are more closely related to each other than to ''Compsemys'', forming the clade Baenoidea. Characteristics Paracryptodires h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helochelydridae
The Helochelydridae are an extinct family of stem-turtles known from fossils found in North America and Europe spanning the Early to Late Cretaceous. Description The skull, shell and osteoderms of helochelydrids are covered in small, cylindrical protuberances, which are a distinctive characteristic of the group. They are thought to be terrestrial, based on the presence of limb osteoderms (granicones) and bone histology. Their skull morphology is dissimilar to that of extant tortoises, suggesting an omnivorous habit similar to that of box turtles. Taxonomy Helochelydridae includes all turtles that are more closely related to '' Helochelydra'' than '' Sichuanchelys'', '' Meiolania'', or extant turtles. Although referred to as Solemydidae in recent literature on extinct turtles, Helochelydridae has priority over Solemydidae. They are placed as part of the clade Perichelydia. Some recent studies have recovered them as paracryptodires, though other studies have found them to be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compsemydidae
Compsemydidae is an extinct family of Testudinata, turtles, likely belonging to the clade Paracryptodira. The earliest undisputed member is ''Tongemys'' from the Berriasian age of the Early Cretaceous; two Late Jurassic genera (''Riodevemys'' and ''Selenemys'') have also sometimes been included in the group, but may alternatively be members of the family Pleurosternidae. The genus ''Compsemys'' survived the Cretaceous–Paleogene extinction event and lasted until the Thanetian age of the Paleocene. Taxonomy Compsemydidae was named in a 2015 paper by Pérez-García ''et al.'', who included the type genus ''Compsemys'' and its possible synonym ''Berruchelus''. A 2020 paper by Joyce and Rollot expanded the family to include the enigmatic ''Peltochelys'' from the Early Cretaceous, as well as the Late Jurassic ''Riodevemys'' and ''Selenemys'' that had earlier been placed in Pleurosternidae. A 2021 paper by Rollot ''et al.'' added the Late Cretaceous ''Kallokibotion'' to the family, b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chisternon
''Chisternon'' is a genus of baenid turtles from the Eocene of North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri .... References *''The Osteology of the Reptiles'' by Alfred Sherwood Romer External links''Chisternon''in the Paleobiology Database Baenidae Prehistoric turtle genera Eocene turtles Eocene reptiles of North America Fossil taxa described in 1872 Taxa named by Joseph Leidy {{paleo-turtle-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Foramina Of The Skull
This article lists Foramen, foramina that occur in the human body. __TOC__ Skull The human skull has numerous openings (foramen, foramina), through which cranial nerves, arteries, veins, and other structures pass. These foramina vary in size and number, with age. Gray193.png , Base of skull, Base of the skull, upper surface Gray187.png , Base of the skull, inferior surface, attachment of muscles marked in red Spine Within the vertebral column (spine) of vertebrates, including the Human vertebral column, human spine, each bone has an opening at both its top and bottom to allow nerves, arteries, veins, etc. to pass through. Other * Apical foramen, the opening at the tip of the root of a tooth * Foramen ovale (heart), an opening between the venous and arterial sides of the fetal heart * Foramen transversarium, one of a pair of openings in each cervical vertebra, in which the vertebral artery travels * Greater sciatic foramen, a major foramen of the pelvis * Interv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Middle Jurassic
The Middle Jurassic is the second Epoch (geology), epoch of the Jurassic Period (geology), Period. It lasted from about 174.1 to 161.5 million years ago. Fossils of land-dwelling animals, such as dinosaurs, from the Middle Jurassic are relatively rare, but geological formations containing land animal fossils include the Forest Marble Formation in England, the Kilmaluag Formation in Scotland,British Geological Survey. 2011Stratigraphic framework for the Middle Jurassic strata of Great Britain and the adjoining continental shelf: research report RR/11/06 British Geological Survey, Keyworth, Nottingham. the Calcaire de Caen of France, the Daohugou Beds in China, the Itat Formation in Russia, the Tiouraren Formation of Niger, and the Isalo III Formation of western Madagascar. Rocks of the Middle Jurassic were formerly (until about 1980s) in Europe called ''Dogger'' or ''Brown Jurassic''. Paleogeography During the Middle Jurassic Epoch, Pangaea began to separate into Laurasia and Gond ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bathonian
In the geologic timescale the Bathonian is an age (geology), age and stage (stratigraphy), stage of the Middle Jurassic. It lasted from approximately 168.2 ±1.2 annum, Ma to around 165.3 ±1.1 Ma (million years ago). The Bathonian Age succeeds the Bajocian Age and precedes the Callovian Age. Stratigraphic definitions The Bathonian Stage takes its name from Bath, Somerset, Bath, a spa town in England built on Jurassic limestone (the Latinized form of the town name is ''Bathonium''). The name was introduced in scientific literature by Belgian geologist Jean Baptiste Julien d'Omalius d'Halloy, d'Omalius d'Halloy in 1843. The original type locality (geology), type locality was located near Bath. The French palaeontologist Alcide d'Orbigny was in 1852 the first to define the exact length of the stage. The base of the Bathonian is at the first appearance of ammonite species ''Parkinsonia (ammonite), Parkinsonia (Gonolkites) convergens'' in the stratigraphic column. The global referen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Forest Marble Formation
The Forest Marble is a geological formation in England. Part of the Great Oolite Group, it dates to the late Bathonian stage of the Middle Jurassic.Weishampel, David B; et al. (2004). "Dinosaur distribution (Middle Jurassic, Europe)." In: Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. Pp. 538–541. . Lithology The primary lithology of the formation typically consists of greenish grey variably calcareous silicate mudstone, with lenticular cross bedded limestone units deposited in a marine setting. Paleobiota Despite the formation being nearly entirely marine, at several localities abundant remains of terrestrial microvertebrates are found, the primary locality being the Kirtlington Mammal Bed (designated 3p) in Kirtlington Quarry near Kirtlington, Oxfordshire. Another important locality is Watton Cliff near Eype in Dorset. Fish Dinosaurs Ornithischians Saurischians Amphi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glyptops Pervicax
''Glyptops'' is an extinct genus of pleurosternid freshwater turtle known from the Late Jurassic of North America. Taxonomy The type species, ''Glyptops plicatulus'', was first described as ''Compsemys plicatulus'' by Edward Drinker Cope on the basis of AMNH 6099, a partial shell from the Late Jurassic (Tithonian) aged Morrison Formation of Colorado. In 1890, a partial skull, YPM 1784 (described from Como Bluff, Wyoming), was named ''Glyptops ornatus'' by Othniel Charles Marsh. Later, Oliver Perry Hay recognized ''Compsemys plicatulus'' and ''Glyptops ornatus'' as being from the same species, hence the new combination ''G. plicatulus''. Another Morrison species of ''Glyptops'', ''G. utahensis'', was described from a complete shell (CM 3412) found at Dinosaur National Monument in Utah. ''Glyptops'' later became a wastebasket taxon to refer to isolated shell fragments with a finely sculpted surface texture. The type of ''Glyptops plicatulus'' was later judged to be a ''nomen dubium ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
