Keuper
Encyclopedia
The Keuper is a lithostratigraphic
unit (a sequence of rock strata) in the subsurface
of large parts of west and central Europe
. The Keuper consists of dolostone
, shale
s or claystone
s and evaporite
s that were deposited during the Middle
and Late Triassic
epoch
s (about ). The Keuper lies on top of the Muschelkalk
and under the predominantly Lower Jurassic Lias
or other Early Jurassic strata.
The Keuper together with the Muschelkalk and the Buntsandstein
, all 3, form the Germanic Trias Group
, a characteristic sequence of rock strata that gave the Triassic
its name.
, Franconia
, Alsace
and Lorraine
and Luxembourg
; it extends from Basel
on the east side of the Rhine into Hanover
, and through England
into Scotland
and north-east Ireland
; it appears flanking the central plateau of France
and in the Pyrenees
and Sardinia
.
In south Sweden
, the lower portion contains coal
-bearing strata, as in the Himalayas
, Japan
, Tibet
, Burma, eastern Siberia
and in Spitsbergen
. The upper portion of the Karoo Supergroup
of South Africa
and part of the Otapiri stage of New Zealand
are probably of Rhaetian age.
The salt
, which is associated with gypsum, is exploited in south Germany at Dreuze, Pettoncourt, as well as in Vie in the Lorraine
region of France. A 4-metre (13 ft) coal is found on this horizon in the Erzgebirge on the border between Germany and the Czech Republic
, and another, 2 metres thick (7 ft), has been mined in Upper Silesia
, now in Poland
.
The Keuper covers a large area in the Midlands
and around the flanks of the Pennine
range; it reaches southward to the Devon
shire coast, eastward into Yorkshire
and northwestward into north Ireland and south Scotland. In the white has the upper hard limestone is known as the sun bed or Jew stone; at the base is the Cotham or landscape marble.
s; the principal plants are cypress
like conifers (Walchia
, Voltzia
) and a few calamites
with such forms as Equisetum arenaceum and Pterophyllum jaegeri. Avicula contorta, Protocardium rhaeticum, Terebratula
gregaria, Myophoria costata, M. goldfassi, Lingula tenuessima, and Anoplophoria lettica may be mentioned among the invertebrates. Fishes include Ceratodus
, Hybodus
and Lepidotus
.
Labyrinthodonts represented by the footprints of Cheirotherium and the bones of Mastodonsaurus
(originally called Labyrinthodon) and Capitosaurus
. Among the reptile
s are Hyperodapedon
, Palaeosaurus
, Zanclodon
, Nothosaurus
and Belodon
. The first fossil mammal
s also make their appearance at this time.
Lithostratigraphy
Lithostratigraphy is a sub-discipline of stratigraphy, the geological science associated with the study of strata or rock layers. Major focuses include geochronology, comparative geology, and petrology...
unit (a sequence of rock strata) in the subsurface
Subsurface
Subsurface is the seventh studio album by British progressive metal band Threshold. The album was released in August 2004, and received an Album of the Month award in several European music magazines....
of large parts of west and central Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
. The Keuper consists of dolostone
Dolostone
Dolostone or dolomite rock is a sedimentary carbonate rock that contains a high percentage of the mineral dolomite. In old U.S.G.S. publications it was referred to as magnesian limestone. Most dolostone formed as a magnesium replacement of limestone or lime mud prior to lithification. It is...
, shale
Shale
Shale is a fine-grained, clastic sedimentary rock composed of mud that is a mix of flakes of clay minerals and tiny fragments of other minerals, especially quartz and calcite. The ratio of clay to other minerals is variable. Shale is characterized by breaks along thin laminae or parallel layering...
s or claystone
Claystone
Claystone is a geological term used to describe a clastic sedimentary rock that is composed primarily of clay-sized particles ....
s and evaporite
Evaporite
Evaporite is a name for a water-soluble mineral sediment that result from concentration and crystallization by evaporation from an aqueous solution. There are two types of evaporate deposits, marine which can also be described as ocean deposits, and non-marine which are found in standing bodies of...
s that were deposited during the Middle
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...
and 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...
epoch
Epoch (reference date)
In the fields of chronology and periodization, an epoch is an instance in time chosen as the origin of a particular era. The "epoch" then serves as a reference point from which time is measured...
s (about ). The Keuper lies on top of the Muschelkalk
Muschelkalk
The Muschelkalk is a sequence of sedimentary rock strata in the geology of central and western Europe. It has a Middle Triassic age and forms the middle part of the Germanic Trias, that further consists of the Buntsandstein and Keuper...
and under the predominantly Lower Jurassic Lias
Lias Group
The Lias Group or Lias is a lithostratigraphic unit found in a large area of western Europe, including the British Isles, the North Sea, the low countries and the north of Germany...
or other Early Jurassic strata.
The Keuper together with the Muschelkalk and the Buntsandstein
Buntsandstein
The Buntsandstein or Bunter sandstone is a lithostratigraphic and allostratigraphic unit in the subsurface of large parts of west and central Europe...
, all 3, form the Germanic Trias Group
Germanic Trias
The Germanic Trias Supergroup is a lithostratigraphic unit in the subsurface of large parts of western and central Europe and the North Sea...
, a characteristic sequence of rock strata that gave the Triassic
Triassic
The Triassic is a geologic period and system that extends from about 250 to 200 Mya . As the first period of the Mesozoic Era, the Triassic follows the Permian and is followed by the Jurassic. Both the start and end of the Triassic are marked by major extinction events...
its name.
Exposure
The Upper Triassic is well exposed in SwabiaSwabia
Swabia is a cultural, historic and linguistic region in southwestern Germany.-Geography:Like many cultural regions of Europe, Swabia's borders are not clearly defined...
, Franconia
Franconia
Franconia is a region of Germany comprising the northern parts of the modern state of Bavaria, a small part of southern Thuringia, and a region in northeastern Baden-Württemberg called Tauberfranken...
, Alsace
Alsace
Alsace is the fifth-smallest of the 27 regions of France in land area , and the smallest in metropolitan France. It is also the seventh-most densely populated region in France and third most densely populated region in metropolitan France, with ca. 220 inhabitants per km²...
and Lorraine
Lorraine (région)
Lorraine is one of the 27 régions of France. The administrative region has two cities of equal importance, Metz and Nancy. Metz is considered to be the official capital since that is where the regional parliament is situated...
and Luxembourg
Luxembourg
Luxembourg , officially the Grand Duchy of Luxembourg , is a landlocked country in western Europe, bordered by Belgium, France, and Germany. It has two principal regions: the Oesling in the North as part of the Ardennes massif, and the Gutland in the south...
; it extends from Basel
Basel
Basel or Basle In the national languages of Switzerland the city is also known as Bâle , Basilea and Basilea is Switzerland's third most populous city with about 166,000 inhabitants. Located where the Swiss, French and German borders meet, Basel also has suburbs in France and Germany...
on the east side of the Rhine into Hanover
Hanover
Hanover or Hannover, on the river Leine, is the capital of the federal state of Lower Saxony , Germany and was once by personal union the family seat of the Hanoverian Kings of Great Britain, under their title as the dukes of Brunswick-Lüneburg...
, and through England
England
England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...
into Scotland
Scotland
Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...
and north-east Ireland
Ireland
Ireland is an island to the northwest of continental Europe. It is the third-largest island in Europe and the twentieth-largest island on Earth...
; it appears flanking the central plateau of France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
and in the Pyrenees
Pyrenees
The Pyrenees is a range of mountains in southwest Europe that forms a natural border between France and Spain...
and Sardinia
Sardinia
Sardinia is the second-largest island in the Mediterranean Sea . It is an autonomous region of Italy, and the nearest land masses are the French island of Corsica, the Italian Peninsula, Sicily, Tunisia and the Spanish Balearic Islands.The name Sardinia is from the pre-Roman noun *sard[],...
.
In south Sweden
Sweden
Sweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....
, the lower portion contains coal
Coal
Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers or veins called coal beds or coal seams. The harder forms, such as anthracite coal, can be regarded as metamorphic rock because of later exposure to elevated temperature and pressure...
-bearing strata, as in the Himalayas
Himalayas
The Himalaya Range or Himalaya Mountains Sanskrit: Devanagari: हिमालय, literally "abode of snow"), usually called the Himalayas or Himalaya for short, is a mountain range in Asia, separating the Indian subcontinent from the Tibetan Plateau...
, Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
, Tibet
Tibet
Tibet is a plateau region in Asia, north-east of the Himalayas. It is the traditional homeland of the Tibetan people as well as some other ethnic groups such as Monpas, Qiang, and Lhobas, and is now also inhabited by considerable numbers of Han and Hui people...
, Burma, eastern Siberia
Siberia
Siberia is an extensive region constituting almost all of Northern Asia. Comprising the central and eastern portion of the Russian Federation, it was part of the Soviet Union from its beginning, as its predecessor states, the Tsardom of Russia and the Russian Empire, conquered it during the 16th...
and in Spitsbergen
Spitsbergen
Spitsbergen is the largest and only permanently populated island of the Svalbard archipelago in Norway. Constituting the western-most bulk of the archipelago, it borders the Arctic Ocean, the Norwegian Sea and the Greenland Sea...
. The upper portion of the Karoo Supergroup
Karoo Supergroup
The Karoo Supergroup is the largest stratigraphic unit in Southern Africa, covering almost two thirds of the present land surface, including central Cape Province, almost all of Orange Free State, western Natal, much of south-east Transvaal, Zambia, Zimbabwe and Malawi...
of South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...
and part of the Otapiri stage of New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...
are probably of Rhaetian age.
Germany
In Germany and adjacent parts of western and central Europe, the Keuper unit is divided into three groups:- Upper Keuper
- The upper part of this division is often a grey dolomiteDolomiteDolomite is a carbonate mineral composed of calcium magnesium carbonate CaMg2. The term is also used to describe the sedimentary carbonate rock dolostone....
known as the Grenz dolomite; the impure coalCoalCoal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers or veins called coal beds or coal seams. The harder forms, such as anthracite coal, can be regarded as metamorphic rock because of later exposure to elevated temperature and pressure...
beds Lettenko/ileare aggregated towards the base. The upper Keuper, Rhaetic or Avicula contorta zone in Germany is mainly sandy with dark grey shaleShaleShale is a fine-grained, clastic sedimentary rock composed of mud that is a mix of flakes of clay minerals and tiny fragments of other minerals, especially quartz and calcite. The ratio of clay to other minerals is variable. Shale is characterized by breaks along thin laminae or parallel layering...
s and marlMarlMarl or marlstone is a calcium carbonate or lime-rich mud or mudstone which contains variable amounts of clays and aragonite. Marl was originally an old term loosely applied to a variety of materials, most of which occur as loose, earthy deposits consisting chiefly of an intimate mixture of clay...
s; it is seldom more than 25 m (82 ft). The sandstones are used for building purposes at Bayreuth, Culmbach and BambergBambergBamberg is a city in Bavaria, Germany. It is located in Upper Franconia on the river Regnitz, close to its confluence with the river Main. Bamberg is one of the few cities in Germany that was not destroyed by World War II bombings because of a nearby Artillery Factory that prevented planes from...
. In Swabia and the Wesergebirge are several boneBoneBones are rigid organs that constitute part of the endoskeleton of vertebrates. They support, and protect the various organs of the body, produce red and white blood cells and store minerals. Bone tissue is a type of dense connective tissue...
-beds, thicker than those in the middle Keuper, which contain a rich assemblage of fossil remains of fish, reptiles and the mammalian teeth of Microlestes antiquus and Triglyptzas Fraasi. The name "Rhaetic" is derived from the Rhaetic Alps where the beds are well developed; they occur also in central France, the Pyrenees and England. In South Tirol and the Judicarian Mountains, the Rhaetic is represented by the Kossenei beds. In the Alpine region, the presence of coral beds gives rise to the so-called Lithodendron Kalk.- Hauptkeuper or Gipskeuper, the middle
- The middle division is thicker than either of the others (at Göttingen, 450 m (1,476.4 ft)); it consists of a marly series below, grey, red and green marls, with gypsumGypsumGypsum is a very soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula CaSO4·2H2O. It is found in alabaster, a decorative stone used in Ancient Egypt. It is the second softest mineral on the Mohs Hardness Scale...
and dolomite—this is the gypskeuper in its restricted sense. The higher part of the series is sandSandSand is a naturally occurring granular material composed of finely divided rock and mineral particles.The composition of sand is highly variable, depending on the local rock sources and conditions, but the most common constituent of sand in inland continental settings and non-tropical coastal...
y, hence called the Steinmergel; it is comparatively free from gypsum. To this division belong the Myophoria beds (M. Raibliana) with galenaGalenaGalena is the natural mineral form of lead sulfide. It is the most important lead ore mineral.Galena is one of the most abundant and widely distributed sulfide minerals. It crystallizes in the cubic crystal system often showing octahedral forms...
in places; the Estheria beds (E. laxilesta); the Schelfsandstein, used as a building-stone; the Lehrherg and Berg-gyps beds; SemionotusSemionotusSemionotus is an extinct genus of ray-finned fish found throughout Northern Pangaea during the late Triassic, becoming extinct at the start of the Jurassic.-External links:...
beds (S. Bergen) with building-stone of CoburgCoburgCoburg is a town located on the Itz River in Bavaria, Germany. Its 2005 population was 42,015. Long one of the Thuringian states of the Wettin line, it joined with Bavaria by popular vote in 1920...
; and the Burgand Stubensandstein.- Kohlenkeuper, Unterkeuper or Lettenkohle, the lower
- The lower division consists mainly of grey clayClayClay is a general term including many combinations of one or more clay minerals with traces of metal oxides and organic matter. Geologic clay deposits are mostly composed of phyllosilicate minerals containing variable amounts of water trapped in the mineral structure.- Formation :Clay minerals...
s and schieferletten with white, grey and brightly colored sandstoneSandstoneSandstone is a sedimentary rock composed mainly of sand-sized minerals or rock grains.Most sandstone is composed of quartz and/or feldspar because these are the most common minerals in the Earth's crust. Like sand, sandstone may be any colour, but the most common colours are tan, brown, yellow,...
and dolomitic limestoneLimestoneLimestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....
.
The salt
Salt
In chemistry, salts are ionic compounds that result from the neutralization reaction of an acid and a base. They are composed of cations and anions so that the product is electrically neutral...
, which is associated with gypsum, is exploited in south Germany at Dreuze, Pettoncourt, as well as in Vie in the Lorraine
Lorraine (région)
Lorraine is one of the 27 régions of France. The administrative region has two cities of equal importance, Metz and Nancy. Metz is considered to be the official capital since that is where the regional parliament is situated...
region of France. A 4-metre (13 ft) coal is found on this horizon in the Erzgebirge on the border between Germany and the Czech Republic
Czech Republic
The Czech Republic is a landlocked country in Central Europe. The country is bordered by Poland to the northeast, Slovakia to the east, Austria to the south, and Germany to the west and northwest....
, and another, 2 metres thick (7 ft), has been mined in Upper Silesia
Upper Silesia
Upper Silesia is the southeastern part of the historical and geographical region of Silesia. Since the 9th century, Upper Silesia has been part of Greater Moravia, the Duchy of Bohemia, the Piast Kingdom of Poland, again of the Lands of the Bohemian Crown and the Holy Roman Empire, as well as of...
, now in Poland
Poland
Poland , officially the Republic of Poland , is a country in Central Europe bordered by Germany to the west; the Czech Republic and Slovakia to the south; Ukraine, Belarus and Lithuania to the east; and the Baltic Sea and Kaliningrad Oblast, a Russian exclave, to the north...
.
Great Britain
In Great Britain the Keuper contains the following subdivisions:- Rhaetic or Penarth
- Grey, red and green marls, black shales, and so-called white (10–150 ft (3–45.7 m)). Upper Keuper marl, red and grey marls and shales with rock salt, 800–3000 ft (243.8–914.4 m). As in Germany, there are one or more bone beds in the English Rhaetic with a similar assemblage of fossils.
- Lower Keuper
- Sandstone, marls and thin sandstones at the top, red and white sandstones (including the so-called waterstones) below, with brecciaBrecciaBreccia is a rock composed of broken fragments of minerals or rock cemented together by a fine-grained matrix, that can be either similar to or different from the composition of the fragments....
s and conglomerates at the base, 150–250 ft (45.7–76.2 m).- Basal conglomerate
- A shore or scree breccia derived from local materials; it is well developed in the MendipMendipMendip is a local government district of Somerset in England. The Mendip district covers a largely rural area of ranging from the Mendip Hills through on to the Somerset Levels. It has a population of approximately 110,000...
district. The rocksalt beds vary from 25 cm (1 inch) to 100 feet (30.5 m) in thickness; they are extensively worked (mined and pumped) in CheshireCheshireCheshire is a ceremonial county in North West England. Cheshire's county town is the city of Chester, although its largest town is Warrington. Other major towns include Widnes, Congleton, Crewe, Ellesmere Port, Runcorn, Macclesfield, Winsford, Northwich, and Wilmslow...
, MiddlesbroughMiddlesbroughMiddlesbrough is a large town situated on the south bank of the River Tees in north east England, that sits within the ceremonial county of North Yorkshire...
and AntrimCounty AntrimCounty Antrim is one of six counties that form Northern Ireland, situated in the north-east of the island of Ireland. Adjoined to the north-east shore of Lough Neagh, the county covers an area of 2,844 km², with a population of approximately 616,000...
.
The Keuper covers a large area in the Midlands
English Midlands
The Midlands, or the English Midlands, is the traditional name for the area comprising central England that broadly corresponds to the early medieval Kingdom of Mercia. It borders Southern England, Northern England, East Anglia and Wales. Its largest city is Birmingham, and it was an important...
and around the flanks of the Pennine
Pennines
The Pennines are a low-rising mountain range, separating the North West of England from Yorkshire and the North East.Often described as the "backbone of England", they form a more-or-less continuous range stretching from the Peak District in Derbyshire, around the northern and eastern edges of...
range; it reaches southward to the Devon
Devon
Devon is a large county in southwestern England. The county is sometimes referred to as Devonshire, although the term is rarely used inside the county itself as the county has never been officially "shired", it often indicates a traditional or historical context.The county shares borders with...
shire coast, eastward into Yorkshire
Yorkshire
Yorkshire is a historic county of northern England and the largest in the United Kingdom. Because of its great size in comparison to other English counties, functions have been increasingly undertaken over time by its subdivisions, which have also been subject to periodic reform...
and northwestward into north Ireland and south Scotland. In the white has the upper hard limestone is known as the sun bed or Jew stone; at the base is the Cotham or landscape marble.
Fossils
The Keuper is not rich in fossilFossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...
s; the principal plants are cypress
Cupressaceae
The Cupressaceae or cypress family is a conifer family with worldwide distribution. The family includes 27 to 30 genera , which include the junipers and redwoods, with about 130-140 species in total. They are monoecious, subdioecious or dioecious trees and shrubs from 1-116 m tall...
like conifers (Walchia
Walchia
Walchia is a fossil conifer, cypress-like genus of Upper Pennsylvanian and lower Permian . It is found in Europe; also North America...
, Voltzia
Voltziales
Voltziales is an extinct order related to modern conifers....
) and a few calamites
Calamites
Calamites is a genus of extinct arborescent horsetails to which the modern horsetails are closely related. Unlike their herbaceous modern cousins, these plants were medium-sized trees, growing to heights of more than 30 meters...
with such forms as Equisetum arenaceum and Pterophyllum jaegeri. Avicula contorta, Protocardium rhaeticum, Terebratula
Terebratula
Terebratula is a modern genus of brachiopod with a fossil record dating back to the Late Devonian. It has a worldwide distribution.-Sources:* Fossils by David Ward -External links:...
gregaria, Myophoria costata, M. goldfassi, Lingula tenuessima, and Anoplophoria lettica may be mentioned among the invertebrates. Fishes include Ceratodus
Ceratodus
Ceratodus was a wide-ranging genus of extinct sarcopterygiian lungfish. Fossil evidence dates back to the Middle Triassic 228 million years ago. A wide range of fossil species from different time periods have been found around the world in places such as the United States, Argentina, England,...
, Hybodus
Hybodus
Hybodus is an extinct genus of once-common, widespread and long lived sharks, first appearing towards the end of the Permian period, and disappearing at the beginning of the Cretaceous. During the Triassic, Jurassic, and Cretaceous periods the hybodonts were especially successful and could be...
and Lepidotus
Lepidotus
Lepidotus is an extinct genus of prehistoric bony fish.-See also:* Prehistoric fish* List of prehistoric bony fish...
.
Labyrinthodonts represented by the footprints of Cheirotherium and the bones of Mastodonsaurus
Mastodonsaurus
Mastodonsaurus was a large-headed temnospondyl that belonged to a group of advanced, mostly Triassic amphibians called capitosaurids. It was a giant among the stegocephalians and the largest animal of its time...
(originally called Labyrinthodon) and Capitosaurus
Capitosaurus
Capitosaurus is an extinct genus of temnospondyl....
. Among the reptile
Reptile
Reptiles are members of a class of air-breathing, ectothermic vertebrates which are characterized by laying shelled eggs , and having skin covered in scales and/or scutes. They are tetrapods, either having four limbs or being descended from four-limbed ancestors...
s are Hyperodapedon
Hyperodapedon
Hyperodapedon is a genus of rhynchosaur from the late Triassic period . The type species of Scaphonyx , Scaphonyx fischeri that once thought to be a dinosaur, is now known to be based on dubious material and therefore should be a nomen dubium...
, Palaeosaurus
Palaeosaurus
Several very different genera of prehistoric animals have been named Palaeosaurus or Paleosaurus since the 1830s. Further confusing the matter, all of the species are poorly known or poorly preserved and both spellings have been used interchangeably, even by the same authors.The repeated recurrence...
, Zanclodon
Zanclodon
Zanclodon is an extinct genus of archosaurian reptile endemic to what would have been Europe during the Middle Triassic-Late Triassic epochs ....
, Nothosaurus
Nothosaurus
Nothosaurus is an extinct genus of sauropterygian reptile from the Triassic period, approximately 240-210 million years ago, with fossils being distributed from North Africa and Europe to China...
and Belodon
Belodon
Belodon is a genus of phytosaur, a crocodile-like reptile that lived during the Triassic. Its fossils have been found in Europe and elsewhere...
. The first fossil mammal
Mammal
Mammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...
s also make their appearance at this time.