Solnhofen Limestone

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Solnhofen Limestone Formation
Stratigraphic range: Kimmeridgian[1]
File:Brittle star fossil.jpg
A brittle star fossil from Solnhofen limestone.
TypeGeological formation
Lithology
PrimaryLimestone
Location
Country Germany

The Solnhofen limestone is a Jurassic Konservat-Lagerstätte that preserves a rare assemblage of fossilized organisms, some of which, such as sea jellies, don't ordinarily fossilize at all. Others, like the early bird Archaeopteryx are preserved in such detail that they are among the most famous and most beautiful fossils in the world. The Solnhofen beds lie in the German state of Bavaria (Bayern), halfway between Nuremberg (Nürnberg) and Munich (München).

Paleoenvironment and preservation

During the Late Jurassic, this area was an archipelago at the edge of the Tethys Sea. This included placid lagoons that had limited access to the open sea and where salinity rose high enough that the resulting brine could not support life. Since the lowest water was devoid of oxygen, many ordinary scavengers were absent. Any organism that fell, drifted, or was washed into the lagoons from the ocean or the land became buried in soft carbonate mud. Thus, many delicate creatures avoided consumption by scavengers or being torn apart by currents. The wings of dragonflies, the imprints of stray feathers, and terrestrial plants that washed into the lagoons were all preserved. The fossils are not numerous, but some of them are spectacular, and their range gives a comprehensive picture of a local Jurassic ecosystem.

At times, the lagoons almost dried out, exposing sticky carbonate muds that trapped insects and even a few small dinosaurs. Over 600 species have been identified, including twenty-nine kinds of pterosaur ranging from the size of a sparrow to 1.2 m (4 ft) in length have been found.

The fine-grained texture of the mud silt forming the limestone from the Solnhofen area (which is composed mainly of the towns of Solnhofen and Eichstätt) is ideal for making lithographic plates, and extensive quarrying in the 19th century revealed many fossil finds, as commemorated in the name Archaeopteryx lithographica, all the specimens of which come from these deposits. The closest modern analogue to the Solnhofen conditions is said to be Orca Basin in the northern Gulf of Mexico, though that area is much deeper than the Solnhofn lagoons.[2]

Fauna

Birds and other dinosaurs

Dinosaurs of the Solnhofen Formation
Taxa Presence Description Images

Genus:

  1. A. lithographica[1]
  2. A. bavarica[1]
  1. Geographically located in Bayern, Germany.[1]
  2. Geographically located in Bayern, Germany.[1]

Genus:

  1. C. longipes[1]
  1. Geographically located in Bayern, Germany.[1]

Superorder:

  1. Possible dinosaur eggs.[1]
  1. Geographically located in Bayern, Germany.[1]

Genus:

  1. W. grandis
  1. Geographically located in Bayern, Germany.[1]

Pterosaurs

Pterosaurs of the Solnhofen Formation
Taxa Presence Notes Images

Genus:

  1. G. cristatus


Genus:

  1. P. antiquus
  2. P. grandis
  3. P. kochi
  4. P. longicollum
  5. P. micronyx
  • The Solnhofen species "P." crassirostris, was given its own genus, Scaphognathus.[3]

Genus:

  1. R. muensteri

Genus:

  1. S. crassirostris[3]
  1. Only two specimens have been recovered from the formation.[3] The first was found in Eichstatt, the second in Mulheim.[3]
  • A Solnhofen genus erected in 1861 by J. A. Wagner when he recognized the rhamphorhynchoid nature of "Pterodactylus" crassirostris after the discovery of a specimen with a preserved tail.[3] The Solnhofen Limestone is the only known source of Scaphognathus fossils.[3]
  1. S. crassirostris was originally named P. crassirostris in 1831 by August Goldfuss who mistook the tailless specimen for a new Pterodactylus species.[3]


Invertrebrate paleofauna

Crinoids

Crinoids of the Solnhofen Formation
Taxa Presence Notes Images

Genus:

  1. S. [4]
  • Saccocoma remains are the most common macroscopic fossils in the Solnhofen limestone.[4]

See also

References

  1. ^ a b c d e f g h i j k l m Weishampel, David B; et al (2004). "Dinosaur distribution (Late Jurassic, Europe)." In: Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. Pp. 545–549. ISBN 0-520-24209-2.
  2. ^ Bartell K.W., Swinburne N.H.M. and Conway-Morris S. 1990. Solnhofen: a study in Mesozoic palaeontology. Cambridge (transl. and revised from Bartel K.W. 1978. Ein Blick in die Erdgeschichte. Ott.
  3. ^ a b c d e f g h "Scaphognathus." In: Cranfield, Ingrid (ed.). The Illustrated Directory of Dinosaurs and Other Prehistoric Creatures. London: Salamander Books, Ltd. Pp. 308-309.
  4. ^ a b c [1]

External links