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| Right humerus NMB M.H. 260, left femur NMB M.H. 372, caudal vertebrae NMB M.H. 280 and NMB M.H. 255, and pedal ungual phalanx NMB M.H. 270, part of the syntype series of Amanzia greppini |
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| Friedrich von Huene (1875-1969), describer of Amanzia greppini |
In the early 1920s, German paleontologist Werner Janensch examined the dinosaur remains unearthed at the Basse Motagne, and while he agreed that the 'Megalosaurus meriani' holotype was from a theropod (meriani was referred to the genus Labrosaurus [a junior synonym of Allosaurus] by Janensch [1920]), he noted that the postcranial remains associated with NHB M.B. 350 were actually referrable to Sauropoda. Based on this information from Janensch, von Huene (1922) described the sauropod remains as a new species of the Early Cretaceous macronarian genus Ornithopsis, O. greppini, the species name honoring the original describer of the sauropod material from the Reuchenette Formation. The syntype series of greppini constitutes as many as four individuals due to the presence of duplicate limb elements. Later, von Huene (1927) realized that O. greppini was generically distinct from the type species of Ornithopsis and referred it to the new eusauropod genus Cetiosauriscus, which is know only from the Middle Jurassic (Callovian) of southern England. Steel (1970) did not consider Cetiosauriscus to be a distinct genus from Cetiosaurus, and thus referred greppini to Cetiosaurus as Cetiosaurus greppini. McIntosh (1990), for his part, followed von Huene (1927) in referring the eusauropod material from the Reuchenette Formation to Cetiosauriscus.
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| Skeletal restoration of Amanzia greppini with preserved elements in blue (from Schwarz et al. 2020) |
Despite being significant as the most complete Jurassic dinosaur from Switzerland, "Ornithopsis" greppini itself received almost no attention in the literature until a review of dinosaur body and trace fossils from Switzerland was published by Meyer and Thüring (2003). They agreed with McIntosh (1990) that greppini is referable to Cetiosauriscus, noting that the two forms share anteroposteriorly short anterior caudal vertebrae and more elongate distal vertebrae, while pointing out that greppini differs from the Cetiosauriscus type species, C. stewarti, in having a more robust humerus whose shaft is proportionally more waisted anteriorly and with a more prominently developed deltopectoral crest. Schwarz et al. (2007a) described the preservation of cartilage in the syntypes of this taxon, and they later (2007b; see also Hofer 2005) indicated that "Ornithopsis" greppini constitutes a new genus of non-neosauropod eusauropod distinct from Cetiosauriscus based of preparation of "O." greppini syntypes by Antoine Heitz. A re-description of the taxon was finally published by Schwarz et al. (2020), who erected the new genus Amanzia for "O." greppini and phylogenetically recovered this taxon as a member of the eusauropod clade Turiasauria. The genus name was chosen to honor Amanz Gressly (1814-1865), who excavated the type material of the basal sauropodomorph Gresslyosaurus ingens in northern Switzerland in the late 1850s.
Although Amanzia was almost neglected by the paleontological community from the time of its initial description until the early 2000s, its journey from a referred specimen of a dubious theropod to being a sauropod, initially as a species of Ornithopsis, Cetiosauriscus, and Cetiosaurus before being finally recognized as a distinct genus in its own right is quite a superfluous one. Considering that the vast majority of sauropod taxa from Kimmeridgian-Tithonian marine deposits in Europe are known only from isolated elements, Amanzia, along with the dwarf macronarian Europasaurus from northwestern Germany, constitute the most complete Late Jurassic sauropods from central Europe. Who knows, one day a diplodocoid or a euhelopodid about as skeletally complete as Amanzia will be found in Late Jurassic marine deposits in western or central Europe.
References:
Greppin, J. P., 1870. Description géologique du Jura bernois et de quelques districts adjacents. Matériaux pour la carte géologique de la Suisse 8: 1–357.
Hofer, C., 2005. Osteologie und Taxonomie von Cetiosauriscus greppini (Huene 1927a, b) aus dem späten Jura von Moutier (Reuchenette Formation) [Osteology and taxonomy of Cetiosauriscus greppini (Huene 1927a, b) from the Late Jurassic of Moutier (Reuchenette Formation)]. Unpublished thesis, University of Basel. 70 pp.
Janensch, W., 1920. Ueber Elaphrosaurus bambergi und die Megalosaurier aus den Tendaguru-Schichten Deutsch-Ostafrikas. Sitzungsberichte der Gesellschaft Naturforschender Freunde zu Berlin 1920: 225–235.
McIntosh, J. S., 1990. Sauropoda. pp. 345-401. In: D. B. Weishampel, P. Dodson, & H. Osmolska (eds.), The Dinosauria. Berkeley: University of California Press.
Meyer, C. A., and Thüring, B., 2003. Dinosaurs of Switzerland. Comptes Rendus Palevol 2: 103–117.
Schwarz, D., Wings, O., and Meyer, C. A., 2007a. Super sizing the giants: first cartilage preservation at a sauropod limb joint. Journal of the Geological Society 164: 61–65.
Schwarz, D., Wings, O., & Meyer, C. A., 2007b. Taxonomische und systematische Revision von Cetiosauriscus greppini (Sauropoda). p. 147. In: O. Elicki & J. W. Schneider (Eds.). Fossile Ökosysteme (Vol. 36). Wissenschaftliche Mitteilungen, Institut für Geologie: Freiberg.
Schwarz, D., Mannion, P.D., Wings, O., and Meyer, C.A., 2020. Re-description of the sauropod dinosaur Amanzia (‘Ornithopsis/Cetiosauriscus’) greppini n. gen. and other vertebrate remains from the Kimmeridgian (Late Jurassic) Reuchenette Formation of Moutier, Switzerland. Swiss Journal of Geosciences 113: 2. https://doi.org/10.1186/s00015-020-00355-5
Steel, R., 1970. Handbuch der Paläoherpetologie/Encyclopedia of Paleoherpetology. Part 14. Saurischia. Stuttgart: Gustav-Fischer-Verlag.
von Huene, F., 1922. Ueber einen Sauropoden im obern Malm des Berner Jura. Eclogae Geologicae Helvetiae 17: 80–94.
von Huene, F., 1927. Short review of the present knowledge of the Sauropoda. Memoirs of the Queensland Museum 9: 121–126.
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