Janenschia

Janenschia
Janenschia fossils in the Berlin Natural History Museum
Temporal occurrence
Upper Jurassic ( Tithonian )
152.1 to 145 million years
Locations
East Africa ( Tendaguru , Tanzania )
Systematics
Sauropods (Sauropoda) Neosauropoda Macronaria Titanosauriformes Titanosaurs (Titanosauria) Janenschia
Scientific name
Janenschia
( Fraas , 1908)
Art
Janenschia robusta

Janenschia is a genus of sauropod dinosaurs (Sauropoda) from the large group of titanosaurs . The only known species is Janenschia robusta , which lived in the late Upper Jurassic ( Tithonian ) in East Africa.

Janenschia was one of the first two dinosaurs to be found in the famous Tendaguru site in Tanzania. Eberhard Fraas originally described the find as Gigantosaurus robustus . It was later discovered that the name Gigantosaurus had already been taken and the species was renamed Tornieria robusta . Eventually it turned out that the animal did not belong to the same genus as Tornieria africana , and so Rupert Wild proposed the new name Janenschia in 1991 in memory of Werner Janensch , the leader of the German Tendaguru expedition.

anatomy

Janenschia was a typical sauropod, tall and with a long neck and tail. It was built very robustly and reached a weight of 15 to 20 tons with a length of about 17 meters.

The animal walked on four columnar legs; the thigh (femur) alone was 1.38 meters long. Janenschia , like other titanosaurs, may have been covered with armored plates, but there is no fossil evidence of this.

Systematics

Janenschia is one of the most primitive as well as the oldest known representatives of the Titanosauria, which makes it particularly important for understanding the origin of this group. The Titanosauria were by far the most successful group of sauropods in the Cretaceous Period, and apparently the only group that survived to the end of this period. They were very common and widespread, especially in Gondwana , and the occurrence of their oldest representative Janenschia in Africa may indicate that their origin is to be sought here as well. Another form sometimes assigned to the same genus is "Gigantosaurus" dixeyi from the Lower Cretaceous of Malawi . This titanosaur is now assigned to its own genus - Malawisaurus .

literature

• José F. Bonaparte , Wolf-Dieter Heinrich, Rupert Wild : Review of Janenschia Wild, with the description of a new sauropod from the Tendaguru beds of Tanzania and a discussion on the systematic value of procoelous caudal vertebrae in the Sauropoda. In: Palaeontographica. Department A: Paleozoology, Stratigraphy. Vol. 256, No. 1/3, 2000, ISSN  0375-0442 , pp. 25-76.
• Eberhard Fraas : East African dinosaurs. In: Palaeontographica. Bd. 55, Lfg. 2, 1908, ZDB -ID 207560-x , pp. 105-144, digitized .
• Werner Janensch : Material and shape content of the sauropods in the yield of the Tendaguru expedition. In: Werner Janensch (ed.): Scientific results of the Tendaguru expedition 1909–1912 (= Palaeontographica. Supplement. Vol. 7, Series 1, Part 2, Lfg. 1, ISSN  0085-4611 ). NF, series 1, part 2, serial 1. Schweizerbart, Stuttgart 1929, pp. 3-34.
• Rupert Wild: Janenschia ng robusta (E. Fraas 1908) per Tornieria robusta (E. Fraas 1908) (Reptilia, Saurischia, Sauropodomorpha) (= Stuttgart contributions to natural history. Series B: Geology and Paleontology. No. 173, ISSN  0341-0153 ). State Museum for Natural History, Stuttgart 1991, digitized version .

Individual evidence

1. ^ ^{A b} Gregory S. Paul : The Princeton Field Guide To Dinosaurs. Princeton University Press, Princeton NJ et al. 2010, ISBN 978-0-691-13720-9 , p. 204, online ( memento of the original from July 13, 2015 in the Internet Archive ) Info: The archive link has been inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. .