Protorosaurus

Drawing of a fossil of Protorosaurus speneri, found at Schweina in Thuringia, today. In Freiberg, trunk, front legs, shoulder girdle

• Thuringia, Saxony -Anhalt, Hesse

Protorosaurus is an extinct lizard- like reptile whose fossil remains have been found in the copper shale in Saxony -Anhalt, Thuringia, North Rhine -Westphalia, Lower Saxony and Hesse. Also from England finds were known early on ( Hancock & Howse, 1871). There were originally described two species, Protorosaurus speneri and Protorosaurus huxleyi. The former was named in honor of Christian Maximilian Spener, who in 1710 described the first copy. The second type, which is only known in one copy of the copper shale equivalent " Marl Slate " of England, was (1988 ) assigned later by Evans due to differences in physique of the genus Adelosaurus.

Discovery history

First fossils were already 1706, 1717/18 and 1733 found in copper Suhl and Glücksbrunn the degradation of copper shale. They were initially described as " marinum amphibium ", " felis marina", petrified crocodile, lizard or fossil lizard. The unusual nature of the finds made ​​during the Enlightenment and the Baroque stir. First pictures can be found shortly after the discovery at Scheuchzer ( 1708), Spener (1710 ), Buettner (1710 ), Mylius (1718 ). The Swiss polymath Johann Jakob Scheuchzer formed the two oldest finds of Protorosaurus from in his treatise on Fishes 1708, and in the copper Bible 1731. For him it was one of the proofs for the correctness of the Flood theory, which was represented by science to the development of the fossils in the 18th century. Subsequent discoveries of ( incompletely preserved ) limbs were - determined to be human remains and created popularly the notion of " Richelsdorfer child's hand " - according to the Flood theory.

According to findings from Thuringia discoveries followed in Rothenburg, Eisleben, Mansfeld and Richelsdorf that were described in the 18th century in part. More recent evidence comes from Bad Sachsa and Ibbenbüren, but also the mining dumps at Eisleben and Richelsdorf offer new finds. Meanwhile, there are at least three complete findings.

Hermann von Meyer gave the reptile in 1832 its still valid scientific name. For a monograph of the copper shale dinosaurs only a few years later in 1856 it were available already 20 copies, but usually only the fuselage and tail fragments of limbs.

A recent revision of Protorosaurus comes from God man & Sander ( 2009).

Features

Protorosaurus was a long-necked lizard that lived in the arid climate on the edge of the Zechstein Sea and was widespread throughout the depositional environment. Countless vegetable remains - ovules of the conifer Ullmannia - in the stomach of a crumbling skeleton discovery were at an early stage of Weigelt (1930 ) interpreted as stomach contents. Schweitzer (1963 ) describes a large coprolites with multiple ovules of Ullmannia from the copper shale equivalent of the Lower Rhine and assigns it to Protorosaurus. Despite this clear evidence of the herbivore diet, suspected Haubold & Schaumberg (1985 ) on the basis of single-pointed teeth a diet of fish.

Only Munk & Sues (1993 ) were able to prove that a vegetarian diet, which is also scientifically accepted today by way of further discovery with plant residues and stomach stones in the stomach. Probably Protorosaurus has the seeds taken specifically of the fallen from the tree mature conifer cones of Ullmannia Frumentaria, because only then the findings of dozens of ovules explained as fossil stomach contents. Ullmannia Frumentaria came in sparse stands on the edge of the Zechstein Sea common and obviously formed an ideal habitat. The associated proximity to the Zechstein Sea explains the frequent finds in the deposits of copper shale and its equivalents.

Protorosaurus had 7 cervical vertebrae, a total of 26 Präsakralwirbel ( vertebrae in front of the pool), two lumbar vertebrae and an estimated 50-70 caudal vertebrae, which previously occupied by a maximum 39 ( Gottmann & Sander 2009). Hermann von Meyer presented at the copper Suhler copy down a length of 1.64 meters. For further fragmentary finds you know that this size was not the maximum attainable size, this is estimated at 2.50 meters. A fund of this size already described the Halle professor Ernst Friedrich Germar in its copper shale fossils monograph in 1840, he comes from Wimmelburg in Eisleben and has just been found in 1839. A similar piece of evidence of a large copy is on display at the Natural History Museum in Schleusingen in Thuringia. Further finds, you can view at the Natural History Museum in Vienna and the Westphalian Museum of Natural History in Münster. Also, the second oldest discovery of copper Suhl from the year 1717/18 you can now: still, in Naturalienkabinett Linck in Waldenburg in Saxony.

In older English literature we find the name used synonymously " Proterosaurus ", which goes back to the paleontological work on the German Zechstein of the Dresden Professor Hanns Bruno Geinitz of 1848 and 1861. This corrected inter alia linguistically ill-formed paleontological name also the name of the Protorosaurus, since the first syllable of the name was derived from the Greek word " Proteros " (first, the first). According to current international rules of nomenclature, but is always the eldest available name binary valid, regardless of a possible incorrect spelling.

System

After Protorosaurus was assigned to the Thecodontia and Rhynchocephalia among other things, he is now placed in the stem lineage of the Archosauria and is considered the oldest known reptile archosauromorphe, so to speak, the ancestor of the ancestors of the dinosaurs.