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Halgaitosaurus
''Halgaitosaurus'' is an extinct genus of araeoscelidian reptile from the late Pennsylvanian (geology), Pennsylvanian of Utah. It contains a single species, ''Halgaitosaurus gregarius'', which is known from the "Virgilian series, Virgilian" (Gzhelian)-age Halgaito Formation in Bears Ears National Monument. The fossils of ''Halgaitosaurus'' include a number of partial skeletons and isolated bones discovered in blocks of siltstone collected from the Birthday Quarry, a multi-taxon Bone bed, bonebed in Valley of the Gods. ''Halgaitosaurus'' makes up about 55% of the fossil material in the 20 blocks recovered from the site. Its fossils show a wide range of body sizes, and their preservation in close company may indicate that it was a gregarious animal, hence the species name. ''Halgaitosaurus'' shows many features in common with araeoscelidians. The Cervical vertebrae, cervical (neck) vertebrae are elongated, and all vertebrae in front of the hip have a midline keel on the underside. Mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Araeoscelidia
Araeoscelidia or Araeoscelida is a clade of extinct tetrapods (traditionally classified as diapsid reptiles) superficially resembling lizards, extending from the Late Carboniferous to the Early Permian. The group contains the genera '' Araeoscelis'', ''Petrolacosaurus'', the possibly aquatic '' Spinoaequalis'', and less well-known genera such as ''Kadaliosaurus'' and '' Zarcasaurus''. This clade is usually considered to be the sister group to all (currently known) later diapsids. Description Araeoscelidians were small animals (less than one meter in length) looking somewhat like lizards, though they are only distantly related to true lizards. They differ from other, earlier sauropsids by their slender limbs, their elongated tail, and of course by the presence of two temporal openings, the feature defining the diapsid condition. In '' Araeoscelis'', only the upper temporal opening remains, thus resulting in a derived euryapsid condition. Genera Araeoscelidia includes well-know ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2023 In Reptile Paleontology
This list of fossil reptiles described in 2023 is a list of new taxa of fossil reptiles that were binomial nomenclature, described during the year 2023, as well as other significant discoveries and events related to reptile paleontology that occurred in 2023. Squamates Squamate research * Redescription of ''Palaeogekko, Palaeogekko risgoviensis'' is published by Villa (2023), who confirms the validity of this species as a distinct taxon, and interprets it as a non-Eublepharidae, eublepharid Gekkonoidea, gekkonoid of uncertain affinities. * Thorn ''et al.'' (2023) describe new fossil material of ''Tiliqua frangens, Aethesia frangens'' from the Pleistocene of Australia, interpret it as a large-bodied (approximately 2.4 kg) blue-tongued skink, and transfer it to the genus ''Tiliqua''. * Lacertidae, Lacertid, blanid and Anguidae, anguid fossil material, including one of the oldest records of the genus ''Blanus'' reported to date, is described from the Early Miocene localities M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pennsylvanian (geology)
The Pennsylvanian ( , also known as Upper Carboniferous or Late Carboniferous) is, on the International Commission on Stratigraphy, ICS geologic timescale, the younger of two period (geology), subperiods of the Carboniferous Period (or the upper of two system (stratigraphy), subsystems of the Carboniferous System). It lasted from roughly . As with most other geochronology, geochronologic units, the stratum, rock beds that define the Pennsylvanian are well identified, but the exact date of the start and end are uncertain by a few hundred thousand years. The Pennsylvanian is named after the U.S. state of Pennsylvania, where the coal Bed (geology), beds of this age are widespread. The division between Pennsylvanian and Mississippian (geology), Mississippian comes from North American stratigraphy. In North America, where the early Carboniferous beds are primarily marine limestones, the Pennsylvanian was in the past treated as a full-fledged geologic period between the Mississippian ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scapula
The scapula (: 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: intrinsic, e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parietal Bone
The parietal bones ( ) are two bones in the skull which, when joined at a fibrous joint known as a cranial suture, form the sides and roof of the neurocranium. In humans, each bone is roughly quadrilateral in form, and has two surfaces, four borders, and four angles. It is named from the Latin ''paries'' (''-ietis''), wall. Surfaces External The external surface [Fig. 1] is convex, smooth, and marked near the center by an eminence, the parietal eminence (''tuber parietale''), which indicates the point where ossification commenced. Crossing the middle of the bone in an arched direction are two curved lines, the superior and inferior temporal lines; the former gives attachment to the temporal fascia, and the latter indicates the upper limit of the muscular origin of the temporal muscle. Above these lines the bone is covered by a tough layer of fibrous tissue – the epicranial aponeurosis; below them it forms part of the temporal fossa, and affords attachment to the temporal mu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Postorbital Bone
The ''postorbital'' is one of the bones in vertebrate skulls which forms a portion of the dermal skull roof and, sometimes, a ring about the orbit. Generally, it is located behind the postfrontal and posteriorly to the orbital fenestra. In some vertebrates, the postorbital is fused with the postfrontal to create a postorbitofrontal. Birds have a separate postorbital as an embryo An embryo ( ) is the initial stage of development for a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male sp ..., but the bone fuses with the frontal before it hatches. References * Roemer, A. S. 1956. ''Osteology of the Reptiles''. University of Chicago Press. 772 pp. Skull bones {{Vertebrate anatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Temporal Fenestra
Temporal fenestrae are openings in the temporal region of the skull of some amniotes, behind the orbit (eye socket). These openings have historically been used to track the evolution and affinities of reptiles. Temporal fenestrae are commonly (although not universally) seen in the fossilized skulls of dinosaurs and other sauropsids (the total group of reptiles, including birds). The major reptile group Diapsida, for example, is defined by the presence of two temporal fenestrae on each side of the skull. The infratemporal fenestra, also called the lateral temporal fenestra or lower temporal fenestra, is the lower of the two and is exposed primarily in lateral (side) view.The supratemporal fenestra, also called the upper temporal fenestra, is positioned above the other fenestra and is exposed primarily in dorsal (top) view. In some reptiles, particularly dinosaurs, the parts of the skull roof lying between the supratemporal fenestrae are thinned out by excavations from the adjacent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nasal Bone
The nasal bones are two small oblong bones, varying in size and form in different individuals; they are placed side by side at the middle and upper part of the face and by their junction, form the bridge of the upper one third of the nose. Each has two surfaces and four borders. Structure There is heavy variation in the structure of the nasal bones, accounting for the differences in sizes and shapes of the nose seen across different people. Angles, shapes, and configurations of both the bone and cartilage are heavily varied between individuals. Broadly, most nasal bones can be categorized as "V-shaped" or "S-shaped" but these are not scientific or medical categorizations. When viewing anatomical drawings of these bones, consider that they are unlikely to be accurate for a majority of people. The two nasal bones are joined at the midline internasal suture and make up the bridge of the nose. Surfaces The ''outer surface'' is concavo-convex from above downward, convex from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frontal Bone
In the human skull, the frontal bone or sincipital bone is an unpaired bone which consists of two portions.'' Gray's Anatomy'' (1918) These are the vertically oriented squamous part, and the horizontally oriented orbital part, making up the bony part of the forehead, part of the bony orbital cavity holding the eye, and part of the bony part of the nose respectively. The name comes from the Latin word ''frons'' (meaning "forehead"). Structure The frontal bone is made up of two main parts. These are the squamous part, and the orbital part. The squamous part marks the vertical, flat, and also the biggest part, and the main region of the forehead. The orbital part is the horizontal and second biggest region of the frontal bone. It enters into the formation of the roofs of the orbital and nasal cavities. Sometimes a third part is included as the nasal part of the frontal bone, and sometimes this is included with the squamous part. The nasal part is between the brow ridges, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maxilla
In vertebrates, the maxilla (: maxillae ) is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. The two maxillary bones are fused at the intermaxillary suture, forming the anterior nasal spine. This is similar to the mandible (lower jaw), which is also a fusion of two mandibular bones at the mandibular symphysis. The mandible is the movable part of the jaw. Anatomy Structure The maxilla is a paired bone - the two maxillae unite with each other at the intermaxillary suture. The maxilla consists of: * The body of the maxilla: pyramid-shaped; has an orbital, a nasal, an infratemporal, and a facial surface; contains the maxillary sinus. * Four processes: ** the zygomatic process ** the frontal process ** the alveolar process ** the palatine process It has three surfaces: * the anterior, posterior, medial Features of the maxilla include: * t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Petrolacosaurus
''Petrolacosaurus'' ("rock lake lizard") is an extinct genus of diapsid reptile from the late Carboniferous period. It was a small, long reptile, and one of the earliest known reptiles with two temporal fenestrae (holes at the rear part of the skull). This means that it was at the base of Diapsida, the largest and most successful radiation of reptiles that would eventually include all modern reptile groups, as well as dinosaurs (which survived to the modern day as birds) and other famous extinct reptiles such as plesiosaurs, ichthyosaurs, and pterosaurs. However, ''Petrolacosaurus'' itself was part of Araeoscelidia, a short-lived early branch of the diapsid family tree which went extinct in the mid-Permian. Discovery The first ''Petrolacosaurus'' fossil was found in 1932 in Garnett, Kansas, by a field expedition from the University of Kansas Natural History Museum. The party consisted of Henry H. Lane, Claude Hibbard, David Dunkle, Wallace Lane, Louis Coghill, and Curtis H ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Araeoscelis
''Araeoscelis'' (from , 'thin' and , 'ribs of beef') is an extinct genus of tetrapods from the Early Permian of what is now Texas. Fossils have been found in the Nocona, Arroyo and Waggoner Ranch Formations. Two species have been described, ''A. casei'' and ''A. gracilis''. ''Araeoscelis'' belonged to the clade Araeoscelidia together with close relatives such as ''Petrolacosaurus''. Araeoscelidia is often considered the most basal group of diapsid reptiles, but some analyses have recovered them as stem-amniotes instead. Description ''Araeoscelis'' was around long, and superficially resembled a modern lizard. It differed from other araeoscelidians, such as ''Petrolacosaurus'', in that its teeth were larger and blunter; possibly they were used for cracking insect carapaces. Unlike ''Petrolacosaurus'', which possessed the two pairs of skull openings characteristic of diapsids, in ''Araeoscelis'' the lower pair of temporal fenestrae were closed with bone, resulting in a e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
