| Tirnovella Temporal range: | |
|---|---|
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Cephalopoda |
| Subclass: | † Ammonoidea |
| Order: | † Ammonitida |
| Family: | † Neocomitidae |
| Subfamily: | † Berriasellinae |
| Subgenus: | † Tirnovella Nikolov, 1966 |
| Type species | |
| † Tirnovella alpillensis Mazenot, 1939 | |
| Species [1] | |
Tirnovella is an extinct subgenus of ammonoid cephalopod, from the early Cretaceous. [2]
The group is often used as an index fossil, with Tirnovella alpillensis being used to define border between the Berriasian and the Valanginian stages of the Cretaceous, and Tirnovella subalpina defining the border between the Middle and Lower substages of the Berriasian. The Middle Berriasian is the defined as the Tirnovella occitanica zone. [3] [4]
Fossils of the genus are relatively common throughout Europe, with fossils from Morocco to Crimea.
The Cretaceous is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of the entire Phanerozoic. The name is derived from the Latin creta, "chalk", which is abundant in the latter half of the period. It is usually abbreviated K, for its German translation Kreide.
The Jurassic is a geologic period and stratigraphic system that spanned from the end of the Triassic Period 201.4 million years ago (Mya) to the beginning of the Cretaceous Period, approximately 145 Mya. The Jurassic constitutes the middle period of the Mesozoic Era and is named after the Jura Mountains, where limestone strata from the period were first identified.
Utahraptor is a genus of large dromaeosaurid dinosaur that lived in North America during the Early Cretaceous period. It was a heavy-built, ground-dwelling, bipedal carnivore. It contains a single species, Utahraptor ostrommaysi, which is one of the largest-known members of the family Dromaeosauridae, measuring 4.9–5.5 m (16–18 ft) long and weighing 280–300 kg (620–660 lb).
In the geological timescale, the Tithonian is the latest age of the Late Jurassic Epoch and the uppermost stage of the Upper Jurassic Series. It spans the time between 152.1 ± 4 Ma and 145.0 ± 4 Ma. It is preceded by the Kimmeridgian and followed by the Berriasian.
In the geological timescale, the Berriasian is an age/stage of the Early/Lower Cretaceous. It is the oldest subdivision in the entire Cretaceous. It has been taken to span the time between 145.0 ± 4.0 Ma and 139.8 ± 3.0 Ma. The Berriasian succeeds the Tithonian and precedes the Valanginian.
In the geologic timescale, the Valanginian is an age or stage of the Early or Lower Cretaceous. It spans between 139.8 ± 3.0 Ma and 132.9 ± 2.0 Ma. The Valanginian Stage succeeds the Berriasian Stage of the Lower Cretaceous and precedes the Hauterivian Stage of the Lower Cretaceous.
In geology, Neocomian was a name given to the lowest stage of the Cretaceous system. It is generally considered to encompass the interval now covered by the Berriasian, Valanginian and Hauterivian, from approximately 145 to 130 Ma. It was introduced by Jules Thurmann in 1835 on account of the development of these rocks at Neuchâtel (Neocomum), Switzerland. It has been employed in more than one sense. In the type area the rocks have been divided into two sub-stages, a lower, Valanginian and an upper, Hauterivian ; there is also another local sub-stage, the infra-Valanginian or Berriasian. These three sub-stages constitute the Neocomian in its restricted sense. Adolf von Koenen and other German geologists extend the use of the term to include the whole of the Lower Cretaceous up to the top of the Gault or Albian. Eugène Renevier divided the Lower Cretaceous into the Neocomian division, embracing the three sub-stages mentioned above, and an Urgonian division, including the Barremian, Rhodanian and Aptian sub-stages. Sir A. Geikie regards Neocomian as synonymous with Lower Cretaceous, and he, like Renevier, closes this portion of the system at the top of the Lower Greensand (Aptian). Other British geologists restrict the Neocomian to the marine beds of Speeton and Tealby, and their estuarine equivalents, the Weald Clay and Hastings Sands (Wealden). Much confusion would be avoided by dropping the term Neocomian entirely and employing instead, for the type area, the sub-divisions given above. This becomes the more obvious when it is pointed out that the Berriasian type is limited to Dauphine; the Valanginian has not a much wider range; and the Hauterivian does not extend north of the Paris basin.
Nuthetes is the name given to a genus of theropod dinosaur, likely a dromaeosaurid, known only from fossil teeth and jaw fragments found in rocks of the middle Berriasian age in the Cherty Freshwater Member of the Lulworth Formation in England and also the Angeac-Charente bonebed in France. As a dromaeosaurid, Nuthetes would have been a small predator.
Rhabdodontidae is a family of herbivorous iguanodontian ornithopod dinosaurs whose earliest stem members appeared in the middle of the Lower Cretaceous. The oldest dated fossils of these stem members were found in the Barremian Castrillo de la Reina Formation of Spain, dating to approximately 129.4 to 125.0 million years ago. With their deep skulls and jaws, Rhabdodontids were similar to large, robust iguanodonts. The family was first proposed by David B. Weishampel and colleagues in 2003. Rhabdodontid fossils have been mainly found in Europe in formations dating to the Late Cretaceous.
Berriasella is a discoidal evolute perisphinctacean ammonite, and type genus for the neocomitid subfamily Berriasellinae. Its ribbing is distinct, consisting of both simple and bifurcated ribs that extend from the umbilical seam across the venter; its whorl section generally compressed, the venter more or less narrowly rounded. The species Berriasella jacobi traditionally has been regarded an index fossil defining the base of the Cretaceous, however since 2016 this had been replaced by the first occurrence of Calpionella alpina. Some authors regard B. jacobi as instead belonging to the genus Strambergella.
Paracryptodira is an extinct group of reptiles in the clade Testudinata, known from the Jurassic to Paleogene of North America and Europe. Initially treated as a suborder sister to Cryptodira, they were then thought to be a very primitive lineage inside the Cryptodira according to the most common use of the latter taxon. They are now often regarded as late-diverging stem-turtles, lying outside the clade formed by Cryptodira and Pleurodira. The paracryptodires are said to have phylogenic relationships, noted as primary subclades, within the Baenidae and Pleurosternidae. Within each subclade, lies many biodiverse turtles that are continuously being investigated and added to the fossil record. 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.
The Villar del Arzobispo Formation is a Late Jurassic to possibly Early Cretaceous geologic formation in eastern Spain. It is equivalent in age to the Lourinhã Formation of Portugal. It was originally thought to date from the Late Tithonian-Middle Berriasian, but more recent work suggests a Kimmeridigan-Late Tithonian, possibly dating to the Early Berriasian in some areas. The Villar del Arzobispo Formation's age in the area of Riodeva in Spain has been dated based on stratigraphic correlations as middle-upper Tithonian, approximately 145-141 million years old. In the area of Galve, the formation potentially dates into the earliest Cretaceous.
Owenodon is a genus of iguanodontian dinosaur known from a partial lower jaw discovered in Early Cretaceous-age rocks of Durlston Bay, Dorset, United Kingdom. The specimen, NHM R2998, comes from the Purbeck Limestone, dating to the middle Berriasian stage. It was first described by Richard Owen, who in 1874 assigned it to Iguanodon as the type specimen of the new species I. hoggii, the specific name honouring naturalist A.J. Hogg who had originally collected the fossil in 1860. The bone was damaged during initial preparation but was freed from the surrounding rock matrix by an acid bath between 1975 and 1977. David Norman and Paul Barrett subsequently transferred the species to Camptosaurus in 2002, but this was challenged, and in 2009 Peter Galton assigned the species to the new genus Owenodon, meaning "Owen's tooth", named after Sir Richard Owen. Galton interpreted the genus as an iguanodontoid more derived than Camptosaurus but less derived than Lurdusaurus.
The Paja Formation is an Early Cretaceous geologic formation of central Colombia. The formation extends across the northern part of the Altiplano Cundiboyacense, the Western Colombian emerald belt and surrounding areas of the Eastern Ranges of the Colombian Andes. In the subsurface, the formation is found in the Middle Magdalena Valley to the west. The Paja Formation stretches across four departments, from north to south the southernmost Bolívar Department, in Santander, Boyacá and the northern part of Cundinamarca. Well known fossiliferous outcrops of the formation occur near Villa de Leyva, also written as Villa de Leiva, and neighboring Sáchica.
Macrobaenidae is an extinct family of turtles, known from the Early Cretaceous to Paleogene of Laurasia. Their relationships to other turtles and whether or not they form a monophlyletic group are controversial. They are typically interpreted as stem or crown group cryptodires, but some more recent analyses have found them to lie outside crown group Testudines. Macrobaenids can be distinguished from other testudinatans by the presence of a carotid fenestra, cruciform plastron with strap-like epiplastra, and a lack of extragulars.
Triunfosaurus is a genus of somphospondylan sauropod dinosaur from the Early Cretaceous of Brazil. It contains a single species, T. leonardii, described by Carvalho et al. in 2017. As a genus, Triunfosaurus can be distinguished from all other titanosaurs by the unique proportions of its ischium. It was initially described as a basal titanosaur, making it the earliest basal titanosaur known; however, subsequent research questioned the identification of the taxon as a titanosaur, instead reassigning it to the Somphospondyli.
Leyvachelys is an extinct genus of turtles in the family Sandownidae from the Early Cretaceous of the present-day Altiplano Cundiboyacense, Eastern Ranges, Colombian Andes. The genus is known only from its type species, Leyvachelys cipadi, described in 2015 by Colombian paleontologist Edwin Cadena. Fossils of Leyvachelys have been found in the fossiliferous Paja Formation, close to Villa de Leyva, Boyacá, after which the genus is named. The holotype specimen is the oldest and most complete sandownid turtle found to date.
The Angeac-Charentebonebed is a fossil deposit located near Angeac-Charente in western France. It dates to the Berriasian stage of the Early Cretaceous, and is coeval with the Purbeck Group of Southern England. It has amongst the most diverse assemblages of earliest Cretaceous vertebrates known from Europe.
Orthophlebiidae is an extinct family of scorpionflies known from the Triassic to Cretaceous, belonging to the superfamily Panorpoidea. The family is poorly defined and is probably paraphyletic, representing many primitive members of Panorpoidea with most species only known from isolated wings, and has such been considered a wastebasket taxon.
Berriasella jacobi is an extinct species of ammonite from the late Jurassic and early Cretaceous. Because of its unique stratigraphic position, it is used as an index fossil to determine the boundary of the Cretaceous and Jurassic periods. The Berriasella jacobi zone defines the substage of the Lower Berriasian, the Berriasian being the lowest stage of the Cretaceous. However, due to the species limited geographic distribution, several other candidates that have been nominated, including Calpionella alpina.
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