Cetiosaurus Greppini

''Amanzia'' (after Swiss geologist Amanz Gressly) is a genus of turiasaurian sauropod dinosaur from the Reuchenette Formation in Moutier, Switzerland. The type and only species is ''Amanzia greppini'', originally named as a species of '' Ornithopsis'' and ''Cetiosauriscus''.

Discovery and naming

The holotype remains were originally discovered in the 1860s, by workers in a limestone quarry in the Basse Montagne. Some of the remains were sold to collectors; when geologist Jean-Baptiste Greppin heard of this situation, he acquired all remaining bones and added them to the collection of the '' Naturhistorisches Museum Basel''. Due to being found in association with the theropod tooth MH 350 found near Moutier that probably belonged to '' Ceratosaurus'' or an indeterminate member of the Ceratosauria, they were misidentified as belonging to a predatory dinosaur, for which Greppin in 1870 coined the name "'' Megalosaurus meriani''" (named after Peter Merian). In 1920, Werner Janensch reassigned the tooth to the genus ''Labrosaurus''. However, in 1922, Janensch realized the vertebrae belonged to a sauropod, so he wrote to Friedrich von Huene, who gave them the name ''Ornithopsis greppini''. In 1927, von Huene assigned the species to his new genus ''Cetiosauriscus''. From then on it has received little attention, with the few papers that mention it usually calling it a ''nomen dubium'' without further comment.

After its fossils were for the first time cleaned and prepared, in 2003 by Antoine Heitz, it was realized not to be closely related to ''Cetiosauriscus''. In 2005, a master thesis by C. Hofer was dedicated to the subject. In 2007, the rare presence of fossilised cartilage in a limb joint was reported.Schwarz, D., Wings, O., & Meyer, C.A. 2007. "Super sizing the giants: first cartilage preservation at a sauropod limb joint". ''Journal of the Geological Society'', 164: 61–65 In 2020, Daniela Schwarz, Philip D. Mannion, Oliver Wings and Christian A. Meyer gave it the genus name ''Amanzia'', after Swiss geologist Amanz Gressly, who was the first to discover dinosaur bones in Switzerland. ''Amanzia'' is itself the first sauropod named from Swiss remains.

In 2020, no lectotype was selected, the naming authors maintaining the original syntype series indicated by von Huene, consisting of forty-nine bones. The Reuchenette Formation in which they were found dates from the early Kimmeridgian, about 157 million years old. They include some neck vertebrae, many tail vertebrae and material from the shoulder girdle, the pelvis and limbs. Seventy-five additional sauropod specimens in the collection of the museum, from the same site as the syntypes, were in 2020 referred to the species. These also include some limited skull material and a broken tooth. The bones are not articulated, have generally been strongly compressed and had often been damaged when being forcefully removed from the rock. Von Huene had already concluded that the material represented two or three individuals; in 2020 this was increased to a minimum of four. Of these, individuals "A" and "B" have about the same size, while an individual "C" is 15% longer and an individual "D" 20% shorter. None of the specimens are clearly juvenile.

References

{{Taxonbar, from=Q86426410

Turiasauria
Late Jurassic dinosaurs of Europe
Kimmeridgian life
Fossils of Switzerland
Fossil taxa described in 2020