Efraasia
Efraasia (pronounced "E-FRAHS-ee-A") is a genus of basal sauropodomorph dinosaur. It was a herbivore which lived during the middle Norian stage of the Late Triassic, around 210 million years ago, in what is now Germany. It was named in 1973 after Eberhard Fraas, who during the early twentieth century collected what were the original type specimens.
The specimens were at first assigned to three already existing genera and so became divided among three separate species: Teratosaurus minor, Sellosaurus fraasi and Paleosaurus diagnosticus. In 2003 these were combined into a single valid species: Efraasia minor.
Efraasia has had a complicated taxonomic history involving several genera and species. Material now known under Efraasia first came to light after Albert Burrer, Hofsteinmetzmeister ("Court master stonemason") at Maulbronn, in 1902 began to exploit the Weiße Steinbruch, a quarry near Pfaffenhofen in Württemberg. To reach the layer of hard white sandstone Burrer wanted to use for his building projects a 6 metres (20 ft) thick overburden of softer marl had to be removed. Many vertebrate fossils proved to be present in it. This stratum was part of the Stubensandstein Member of the lower Löwenstein Formation, dating to the Norian. From 1906 until 1914 when the quarry closed, Burrer donated the finds to paleontologist Professor Fraas of the königliche Stuttgarter Naturalienkabinett.
A specimen of a basal sauropodomorph, SMNS 11838, was first described by Friedrich von Huene in 1907–1908 and named as a new species of Teratosaurus: T. minor. At the time, Teratosaurus was thought to be a theropod dinosaur; it was only established as a rauisuchian non-dinosaur in the 1980s. The specific name referred to the fact that the specimen was smaller than Teratosaurus suevicus. The fossils consisted of a few vertebrae from the hip, the right hindlimb, and a pubic bone. Elsewhere in the same publication he gave the name Sellosaurus fraasi to a partial skeleton, SMNS 12188-12192, from slightly older rocks of the same formation, as a second species of his new genus Sellosaurus (the genus is today considered to be a synonym of Plateosaurus).[1]
In 1912, Eberhard Fraas reported on two partial skeletons, SMNS 12667 and SMNS 12684 collected in 1909, which he assigned to a new species of Thecodontosaurus: T. diagnosticus.[2] He would never describe them due to his failing health, and thus this name remained a nomen nudum. Von Huene adopted the specific name years later, after Fraas' death, redescribing Fraas' specimens as Paleosaurus (?) diagnosticus in 1932.[3] The question mark indicates that von Huene considered the reference as provisional only. In 1959 Oskar Kuhn pointed out that the name Paleosaurus Riley & Stutchbury 1836 was preoccupied and renamed the genus Palaeosauriscus.[4] Allen Charig in 1967 was the first to use the combination Palaeosauriscus diagnosticus for the German material.[5] However, the new generic name was itself a junior homonym of Palaeosauriscus fraserianus Cope 1878.
Peter Galton reassigned Fraas' specimens to the new genus Efraasia in 1973, because Palaeosaurus, apart from the homonymy problems, was a nondiagnostic tooth genus. The generic name was a contraction of "E. Fraas". The new species name combination thus became Efraasia diagnostica.[6] However, Galton and Robert Bakker later (1985) recommended that Efraasia be considered a junior synonym of another prosauropod, Sellosaurus gracilis.[7][8]
