Tithonian

In the geologic timescale the Tithonian is the latest age of the Late Jurassic epoch or the uppermost stage of the Upper Jurassic series. It spans the time between 150.8 ± 4 Ma and 145.5 ± 4 Ma (million years ago). It is preceded by the Kimmeridgian and followed by the Berriasian stage (part of the Cretaceous).^[1]

Stratigraphic definitions

The Tithonian was introduced in scientific literature by German stratigrapher Albert Oppel in 1865. The name Tithonian is unusual in geological stage names because it is derived from Greek mythology. Tithonus was the son of Laomedon of Troy. He fell in love with Eos, the Greek goddess of dawn and finds his place in the stratigraphy because this stage, the Tithonian, finds itself hand in hand with the dawn of the Cretaceous.

The base of the Tithonian stage is at the base of the ammonite biozone of Hybonoticeras hybonotum. A global reference profile (a GSSP or golden spike) for the base of the Tithonian had in 2009 not yet been established.

The top of the Tithonian stage (the base of the Berriasian stage and the Cretaceous system) is at the first appearance of fossils of ammonite species Berriasella jacobi in the stratigraphic record.

Subdivision

The Tithonian is often subdivided into Lower/Early, Middle and Upper/Late substages or subages. The Late Tithonian is coeval with the Portlandian stage of British stratigraphy.

The Tithonian stage contains seven ammonite biozones in the Tethys domain, from top to base:

• zone of Durangites
• zone of Micracanthoceras micranthum
• zone of Micracanthoceras ponti or Burckardticeras peroni
• zone of Semiformiceras fallauxi
• zone of Semiformiceras semiforme
• zone of Semiformiceras darwini
• zone of Hybonoticeras hybonotum

Lithofacies

In the Tethys domain, the Tithonian has a calcareous facies with a typical cephalopod fauna. The Solnhofen limestone of southern Germany, which is known for its fossils (especially Archaeopteryx), is of Tithonian age.

Palaeontology

Ankylosaurs

Ankylosauria of the Tithonian
Taxa	Presence	Location	Description	Images
Gargoyleosaurus		Morrison Formation, Wyoming, USA	The smallest and the earliest well-known ankylosaur. Its skull measures only 29 cm in length, and its total body length is an estimated three to four meters.	Gargoyleosaurus skeleton
Mymoorapelta Mymoorapelta maysi		Morrison Formation, Colorado, USA	A poorly known early ankylosaurian.

Ceratopsians

Ceratopsia of the Tithonian
Taxa	Presence	Location	Description	Images
Chaoyangsaurus	?	Chaoyang area, Liaoning, China	One of the earliest ceratopsians	Chaoyangsaurus
Xuanhuaceratops		Hebei, China	A member of the family Chaoyangsauridae, it was one of the earliest ceratopsians

Ornithopods

Ornithopoda of the Tithonian
Taxa	Presence	Location	Description	Images
Camptosaurus	Kimmeridgian to ?Berriasian	Wyoming, USA; England; France	Camptosaurus could be more than 7.9 meters long (26 ft), and 2.0 meters tall (6.7 ft) at the hips. They had heavy bodies but, as well as walking on four legs (quadrupedal), could also rear up to walk on two legs (bipedal). This genus is probably closely related to the ancestor of the later iguanodontid and hadrosaurid dinosaurs. It probably ate cycads with its parrot-like beak.	Camptosaurus Dryosaurus Othnielosaurus
Draconyx		Lourinhã, Portugal	A camptosaurid iguanodont
Drinker
Dryosaurus
Othnielia
Othnielosaurus

Plesiosauria

Plesiosaurs of the Tithonian
Taxa	Presence	Location	Description	Images
Simolestes indicus				Simolestes

Stegosaurs

Stegosaurs of the Tithonian
Taxa	Presence	Location	Description	Images
Stegosaurus	Kimmeridgian to Early Tithonian	Morrison Formation, Colorado, Utah, Wyoming, USA	Averaging around 9 metres (30 ft) long and 4 metres (14 ft) tall, the quadrupedal Stegosaurus is one of the most easily identifiable dinosaurs, due to the distinctive double row of kite-shaped plates rising vertically along its arched back and the two pairs of long spikes extending horizontally near the end of its tail.	Stegosaurus

Sauropoda

Sauropoda of the Tithonian
Taxa	Presence	Location	Description	Images
Apatosaurus				Apatosaurus Diplodocus Mamenchisaurus
Diplodocus
Mamenchisaurus

Thalattosuchians

Thalattosuchians of the Tithonian
Taxa	Presence	Location	Description	Images
Dakosaurus Dakosaurus maximus Dakosaurus andiniensis			A large genus of metriorhynchid, that was a high order predator which fed on other marine reptiles The type species from Western Europe of the Late Jurassic (Early Tithonian). Argentina of the Late Jurassic-Early Cretaceous (Early Tithonian), knicknamed "Godzilla".	Dakosaurus, a marine crocodilian. Geosaurus, a marine crocodilian. Metriorhynchus, a marine crocodilian.
Geosaurus G. giganteus G. gracilis G. suevicus: G. saltillense: G. vignaudi: G. araucanensis:		Western Europe Western Europe Western Europe Mexico Mexico Argentina	A relatively small metriorhynchid genus. No known species of Geosaurus attained lengths in excess of 3 meters (10 feet). There were multiple Geosaurus species alive during the Tithonian. The type species from Western Europe of the Late Jurassic (Early Tithonian). Western Europe of the Late Jurassic (Early Tithonian). Was originally the type species of the genus Rhacheosaurus. Western Europe of the Late Jurassic (Early Tithonian) Mexico of the Late Jurassic (Early Tithonian) Mexico of the Late Jurassic (Middle Tithonian) Argentina of the Late Jurassic-Early Cretaceous (Early Tithonian)
Machimosaurus
Metriorhynchus M. potens			An opportunistic carnivore that fed on fish, belemnites and other marine animals and possible carrion. Metriorhynchus grew to an average adult length of 3 meters (9.6 feet).
Steneosaurus

Belemnites

Belemnites of the Tithonian
Taxa	Presence	Location	Description	Images
Produvalia				Small belemnite fossils

References

Notes

Literature

• Gradstein, F.M.; Ogg, J.G. & Smith, A.G.; (2004): A Geologic Time Scale 2004, Cambridge University Press.
• Oppel, C.A.; 1865: Die Tithonische Etage, Zeitschrift der Deutschen Geologischen Gesellschaft, 1865: pp 535-558. (German)

External links

• GeoWhen Database - Tithonian
• Jurassic-Cretaceous timescale, at the website of the subcommission for stratigraphic information of the ICS
• Stratigraphic chart of the Upper Jurassic, at the website of Norges Network of offshore records of geology and stratigraphy