The Ladinian is a stage and age in the Middle Triassic

Middle Triassic

In the geologic timescale, the Middle Triassic is the second of three epochs of the Triassic period or the middle of three series in which the Triassic system is divided. It spans the time between 245 ± 1.5 Ma and 228 ± 2 Ma...

 series

Series (stratigraphy)

Series are subdivisions of rock layers made based on the age of the rock and corresponding to the dating system unit called an epoch, both being formally defined international conventions of the geological timescale. A series is therefore a sequence of rock depositions defining a...

 or epoch

Epoch (geology)

An epoch is a subdivision of the geologic timescale based on rock layering. In order, the higher subdivisions are periods, eras and eons. We are currently living in the Holocene epoch...

. It spans the time between 237 ± 2 Ma and 228 ± 2 Ma (million years ago). The Ladinian was preceded by the Anisian

Anisian

In the geologic timescale, the Anisian is the lower stage or earliest age of the Middle Triassic series or epoch and lasted from 245 million years ago until 237 million years ago, approximately...

 and succeeded by the Carnian

Carnian

The Carnian is the lowermost stage of the Upper Triassic series . It lasted from about 228.7 till 216.5 million years ago . The Carnian is preceded by the Ladinian and is followed by the Norian...

 (part of the Upper or Late Triassic

Late Triassic

The Late Triassic is in the geologic timescale the third and final of three epochs of the Triassic period. The corresponding series is known as the Upper Triassic. In the past it was sometimes called the Keuper, after a German lithostratigraphic group that has a roughly corresponding age...

).

The Ladinian is coeval with the Falangian Chinese

China

Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...

 regional stage.

Stratigraphic definitions

The Ladinian was established by Austrian geologist Alexander Bittner in 1892. Its name comes from the Ladin people that live in the Italian

Italy

Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...

 Alps

Alps

The Alps is one of the great mountain range systems of Europe, stretching from Austria and Slovenia in the east through Italy, Switzerland, Liechtenstein and Germany to France in the west....

 (in the Dolomites

Dolomites

The Dolomites are a mountain range located in north-eastern Italy. It is a part of Southern Limestone Alps and extends from the River Adige in the west to the Piave Valley in the east. The northern and southern borders are defined by the Puster Valley and the Sugana Valley...

, then part of Austria-Hungary

Austria-Hungary

Austria-Hungary , more formally known as the Kingdoms and Lands Represented in the Imperial Council and the Lands of the Holy Hungarian Crown of Saint Stephen, was a constitutional monarchic union between the crowns of the Austrian Empire and the Kingdom of Hungary in...

).

The base of the Ladinian stage is defined as the place in the stratigraphic record where the ammonite

Ammonite

Ammonite, as a zoological or paleontological term, refers to any member of the Ammonoidea an extinct subclass within the Molluscan class Cephalopoda which are more closely related to living coleoids Ammonite, as a zoological or paleontological term, refers to any member of the Ammonoidea an extinct...

 species Eoprotrachyceras curionii first appears. The global reference profile for the base (the GSSP) is at an outcrop

Outcrop

An outcrop is a visible exposure of bedrock or ancient superficial deposits on the surface of the Earth. -Features:Outcrops do not cover the majority of the Earth's land surface because in most places the bedrock or superficial deposits are covered by a mantle of soil and vegetation and cannot be...

 in the river bed of the Caffaro

Caffaro

Caffaro may refer to:*Caffaro , a river in north Italy*Caffaro di Rustico da Caschifellone , a Genoan crusader and chronicler...

 river at Bagolino

Bagolino

Bagolino is a comune in the province of Brescia, in Lombardy, Italy, in the valley of the river Caffaro, on the right side of Valle Sabbia. Bagolino is famous for the cheese named Bagòss and the carnival....

, in the province of Brescia

Province of Brescia

The Province of Brescia is a Province in Lombardy, Italy. It borders with the province of Sondrio in the N and NW, the province of Bergamo in the W, province of Cremona in the SW and S, the province of Mantova to the S, and to the east, the province of Verona and Trentino .Source for statistical...

, northern Italy

Italy

Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...

. The top of the Ladinian (the base of the Carnian) is at the first appearance of ammonite species Daxatina canadensis.

The Ladinian is sometimes subdivided into two subages or substages, the Fassanian (early or lower) and the Longobardian (late or upper). The Ladinian contains four ammonite biozones, which are evenly distributed among the two substages:

• zone of Frechites regoledanus
  Frechites
  Frechites is an early Triassic ammonite, a kind of cephalopod with an external shell, included in the ceratitid family Beyrichitidae.-Taxonomic revision:...
  
  
• zone of Protrachyceras archelaus
• zone of Protrachyceras gredleri
• zone of Eoprotrachyceras curionii

Palaeontology

Many Ladinian and Carnian vertebrates have been discovered in the paleorrota

Paleorrota

Paleorrota , is a geopark located in the center of the Brazilian state of Rio Grande do Sul. The rocks and fossils found along the route date back to the times when there was only one supercontinent Pangaea....

 in Brazil

Brazil

Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...

: Rhynchosaur

Rhynchosaur

Rhynchosaurs were a group of Triassic diapsid reptiles related to the archosaurs.-Description:Rhynchosaurs were herbivores, and at times abundant , with stocky bodies and a powerful beak...

s, thecodont

Thecodont

Thecodont , now considered an obsolete term, was formerly used to describe a diverse range of early archosaurs that first appeared in the Latest Permian and flourished until the end of the Triassic period...

s, exaeretodonts, Staurikosaurus

Staurikosaurus

Staurikosaurus is a genus of herrerasaurid dinosaur from the Late Triassic of Brazil.-Discovery:The first known specimen of Staurikosaurus was recovered from the Paleontological Site Jazigo Cinco of the Santa Maria Formation in the geopark of paleorrota , Rio Grande do Sul, southern Brazil...

, Guaibasaurus

Guaibasaurus

Guaibasaurus is an extinct genus of basal dinosaur known from the Triassic of Rio Grande do Sul, southern Brazil.-Discovery:Guaibasaurus was originally named on the basis of the holotype, MCN PV2355, a well-preserved partial postcranial skeleton and the paratype, MCN PV2356, an...

, Saturnalia tupiniquim, Sacisaurus

Sacisaurus

Sacisaurus is a dinosauriform from the Late Triassic Caturrita Formation of southern Brazil...

, Unaysaurus

Unaysaurus

Unaysaurus is a genus of sauropodomorph dinosaur, and is one of the oldest dinosaurs known. It was discovered in southern Brazil,in the geopark of paleorrota, in 1998, and announced in a press conference on Thursday, December 3, 2004...

, and many others. Paleorrota

Paleorrota

Paleorrota , is a geopark located in the center of the Brazilian state of Rio Grande do Sul. The rocks and fossils found along the route date back to the times when there was only one supercontinent Pangaea....

 lies within the Santa Maria Formation

Santa Maria Formation

The Santa Maria Formation is a sedimentary rock formation found in Rio Grande do Sul, Brazil. It has a late Ladinian – early Carnian age , and is notable for its fossils of early dinosaurs, including the herrerasaur Staurikosaurus, the basal saurischian Teyuwasu, and the basal sauropodomorph...

 and the Caturrita Formation

Caturrita Formation

The Caturrita Formation is a rock formation found in Rio Grande do Sul, Brazil. Its sediments were deposited in the Paraná Basin. The formation has a late Carnian to early Norian age and forms part of the Santa Maria Supersequence in the upper section of the Rosário do Sul Group.-Etymology:The...

.

Vertebrates of Ladinian age include:

• Spondylosoma
  Spondylosoma
  Spondylosoma is a genus of archosaur of uncertain affinities from the late Ladinian-age Middle Triassic Lower Santa Maria Formation in Geopark of Paleorrota, Brazil. Recent studies have gone back and forth on its identity, suggesting rauisuchian or basal saurischian dinosaur...
  
  
• Dicynodonts

†Dinosauromorphs (non-dinosaurian)

†Non-dinosaurian Paraphyly A group of taxa is said to be paraphyletic if the group consists of all the descendants of a hypothetical closest common ancestor minus one or more monophyletic groups of descendants...  dinosauromorphs Dinosauromorpha Dinosauromorpha is the name of a clade of archosaurs that includes the closest relatives of dinosaurs, and the order Dinosauria itself. Basal forms include Saltopus, Marasuchus, the perhaps identical Lagosuchus, the lagerpetonids Lagerpeton from the Ladinian of Argentina and Dromomeron from the...  of the Ladinian
Taxa	Presence	Location	Description	Images
Lagerpeton Lagerpeton Lagerpeton is a genus of basal dinosauromorph from the Ladinian . Lagerpeton is known from several specimens of hindlimbs, hips, vertebrae, and feet. It was about 0.7 metres long and was found in the Chañares Formation of Argentina. It has unique feet, with an unusually long fourth toe...		Chañares Formation Chañares Formation The Chañares Formation in La Rioja Provence, Argentina, dates to the Anisian stage of the early Middle Triassic.Some localities are well known for their abundance of tetrapods. Theraspids include the kannemeyeriid Dinodontosaurus, and cynodonts such as Probainognathus and Massetognathus, the latter... , Argentina
Lagosuchus Lagosuchus Lagosuchus is a genus of small archosaur from the middle Triassic period. It is generally thought to be closely related to dinosaurs, as a member of the Dinosauromorpha...		Argentina

†Placodonts

Placodonts of the Ladinian
Taxa	Presence	Location	Description	Images
Cyamodus Cyamodus Cyamodus was a placodont, known from fossil remains discovered in Germany, in the early-to-mid-19th century and was named by Christian Erich Hermann von Meyer, in 1863. The fossils have been dated to the Triassic Period, from the Anisian to Ladinian stages...
Paraplacodus Paraplacodus Paraplacodus was a Placodont from the middle Triassic period, during the Anisian to Ladinian stages. The fossils were uncovered in Northern Italy and the species was named in 1931 by Bernhard Peyer. Paraplacodus means "Almost Placodus", and thus far only one species, P...

†Therapsids (non-mammalian)

†Non-mammalian Paraphyly A group of taxa is said to be paraphyletic if the group consists of all the descendants of a hypothetical closest common ancestor minus one or more monophyletic groups of descendants...  Therapsids of the Ladinian
Taxa	Presence	Location	Description	Images
Exaeretodon Exaeretodon Exaeretodon is a genus of traversodontid cynodont; several species are known, from various formations. E. argentinus, E. frenguelli, and E. vincei are from the Carnian-age Ischigualasto Formation of Argentina. E. major and E. riograndensis are from the Ladinian-age portion of the Santa Maria...

Literature

; 1892: Was ist norisch?, Jahrbuch der kaiserlich-königlichen geologischen Reichsanstalt 42(3), pp. 387-396. ; 2005: The Global boundary Stratotype Section and Point (GSSP) of the Ladinian Stage (Middle Triassic) at Bagolino (Southern Alps, Northern Italy) and its implications for the Triassic time scale, Episodes 28(4), pp. 233-244.; 2004: A Geologic Time Scale 2004, Cambridge University Press

Cambridge University Press

Cambridge University Press is the publishing business of the University of Cambridge. Granted letters patent by Henry VIII in 1534, it is the world's oldest publishing house, and the second largest university press in the world...

.

External links

• GeoWhen Database - Ladinian
• Upper Triassic and Lower Triassic timescales, at the website of the subcommission for stratigraphic information of the ICS
• Norges Network of offshore records of geology and stratigraphy: Stratigraphic charts for the Triassic, http://norges.uio.no/timescale/Late_Triassic.pdf and http://norges.uio.no/timescale/Fig16.1_Tri_colB.pdf