Ensiklopedia Dunia

Technopedia Center

Faculty of Engineering and Computer Science
S1 Informatics S1 Information Systems S1 Information Technology S1 Computer Engineering S1 Electrical Engineering S1 Civil Engineering

faculty of Economics and Business
S1 Management S1 Accountancy

Faculty of Letters and Educational Sciences
S1 English literature S1 English language education S1 Mathematics education S1 Sports Education

Eretmosaurus - Wikipedia

From Wikipedia, the free encyclopedia

Eretmosaurus Temporal range: Early - Middle Jurassic, 199.5–161.5 Ma PreꞒ Ꞓ O S D C P T J K Pg N

Neotype specimen of E. rugosus
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Superorder:	†Sauropterygia
Order:	†Plesiosauria
Family:	†Microcleididae
Genus:	†Eretmosaurus Seeley, 1874
Type species
†Eretmosaurus rugosus Seeley, 1874
Other species
†E. dubius Blake in Tate & Blake, 1876
Synonyms
Erethmosaurus von Huene, 1956 Plesiosaurus dubius Tate & Blake, 1876 Plesiosaurus rugosus Owen, 1840

Eretmosaurus (meaning "oar lizard") is an extinct genus of plesiosaur from the Early and Middle Jurassic of England and Russia.^[1]^[2] Two species are known: E. rugosus and E. dubius.

History

Eretmosaurus rugosus

c. 1870 illustration of the holotype of *E. rugosus*

The holotype of E. rugosus consists of vertebrae, girdles, and limb bones and was discovered along Aust Cliff, where the Westbury Formation outcrops. Specimen BRSMB Cb 2458 was also assigned to the species by Owen (1840).^[3] This specimen later became the syntype and it consisted of several vertebrae that had been discovered at different locations in the Blue Lias in Gloucestershire.

Owen (1840) was the first to describe the specimens, which were named as Plesiosaurus rugosus.^[3] Later, Owen (1865) described a headless skeleton discovered in the Ammonites stellaris zone of the Blue Lias at Granby, Nottinghamshire (NHMUK 14435) that he assigned to P. rugosus,^[4] and Seeley used NHMUK 14435 as the basis for naming Eretmosaurus rugosus in 1874.^[5]

As BRSMB Cb 2458 was not diagnostic and was lost by 1940, a petition was filed with the ICZN over the holotype by Brown and Bardet (1994),^[1] and NHMUK 14435 was allocated as the official neotype in 1996.^[6]

A fragmentary specimen of Eretmosaurus rugosus has also been identified from the Middle Jurassic of Siberia by Menner (1992).^[2]

Eretmosaurus dubius

A partial skull and skeleton belonging to a plesiosaur was discovered in the Harpoceras faleifer zone, Whitby, England and it was initially described by Blake & Tate (1876) as a species of Plesiosaurus known as P. dubius. It was later reclassified as a species of Eretmosaurus by Blake in Blake & Tate (1876).^[7]

Other species

Benton and Spencer (1995) mentioned a third species of Eretmosaurus: E. macropterus; they rectified this mistake within the same paper by mentioning on page 116 that E. macropterus actually belongs to Microcleidus.^[8]

Classification

Eretmosaurus was classified into Rhomaleosauridae by Persson (1963),^[9] then into Pliosauridae by Brown (1981),^[10] then into Elasmosauridae by Bardet (1995)^[11] and Bardet et al. (1999),^[12] and most recently into Microcleididae by Benson et al. (2012).^[13]

References

^ ^a ^b David S. Brown and Nathalie Bardet (1994). Plesiosaurus rugosus Owen, 1840 (currently Eretmosaurus rugosus, Reptilia, Plesiosauria) proposed designation of a neotype. Bulletin of Zoological Nomenclature 51(3)
^ ^a ^b Menner, V. V. (1992). "Remains of Plesiosaurs from Middle Jurassic Deposits of Eastern Siberia". Russian Academy of Sciences, Department of Geology, Geophysics, Geochemistry and Mining Sciences, Order of the Red Manner of Labour Geological Institute: 74–91.
^ ^a ^b R. Owen. (1840). Report on British fossil reptiles. Report of the Ninth Meeting of the British Association for the Advancement of Science, Reports on the State of Science 43-126
^ R. Owen. (1865). A monograph of the fossil Reptilia of the Liassic formations. Part I, Sauropterygia. Palaeontographical Society Monographs 17(75):1-40
^ Seeley, H. G., (1874), Note on some of the generic modifications of the plesiosaurian pectoral arch: Quarterly Journal of the Geological Society of London, 1874, p. 436-449.
^ David S. Bown and Nathalie Bardet (1996). Plesiosaurus rugosus Owen, 1840 (currently Eretmosaurus rugosus, Reptilia, Plesiosauria) neotype designated. Bulletin of Zoological Nomenclature 51(3)
^ Blake, John F.; Tate, Ralph (1876). The Yorkshire Lias. University of California. ISBN 9789333163415.
^ Benton, M. J. and Spencer, P. S. (1995). Fossil reptiles of Great Britain. Chapman and Hall, London, 386 pp.
^ Persson, P.O. (1963): A revision of the classification of the Plesiosauria, with a synopsis of the stratigraphical and geographical distribution of the group. University of Lunds Årsskrift 59, No. 1, p. 1-57.
^ Brown, D. S. (1981). The English Upper Jurassic Plesiosauroidea (Reptilia) and a review of the phylogeny and classification of the Plesiosauria. Bulletin of the British Museum (Natural History): Geology, 35, (4), 253-347.
^ Bardet, N. (1995). Evolution et extinction des reptiles marins au cours du Mésozoïque. Palaeovertebrata, 24, 177-283.
^ Bardet, N.; Godefroit, P.; and Sciau, J. (1999). A new elasmosaurid plesiosaur from the Lower Jurassic of Southern France. Palaeontology'", 42, (5), 927-952.
^ Benson, Roger B. J.; Evans, Mark; Druckenmiller, Patrick S. (2012-03-16). Lalueza-Fox, Carles (ed.). "High Diversity, Low Disparity and Small Body Size in Plesiosaurs (Reptilia, Sauropterygia) from the Triassic–Jurassic Boundary". PLOS ONE. 7 (3): e31838. Bibcode:2012PLoSO...731838B. doi:10.1371/journal.pone.0031838. ISSN 1932-6203. PMC 3306369. PMID 22438869.

Sauropterygia

Kingdom: Animalia
Phylum: Chordata
Class: Sauropsida
Subclass: Diapsida
Clade: Neodiapsida

Sauropsida

- see Sauropsida

Sauropterygia	see below↓

Sauropterygia

Helveticosauridae?

Eusaurosphargis?
Helveticosaurus

Saurosphargidae

Placodontia

Paraplacodus Pararcus Placodus
Cyamodontoidea	Cyamodus Glyphoderma Henodus Macroplacus Parahenodus Placochelys Protenodontosaurus Psephochelys Psephoderma Psephosauriscus Psephosaurus Sinocyamodus

Eosauropterygia

- see below↓

Eosauropterygia

Corosaurus
Cymatosaurus

Pachypleurosauria

Nothosauroidea

Brevicaudosaurus Hispaniasaurus? Sanchiaosaurus
Simosauridae	Paludidraco Simosaurus
Nothosauridae	Ceresiosaurus Germanosaurus Lariosaurus Metanothosaurus Nothosaurus Proneusticosaurus Silvestrosaurus

Pistosauroidea

Augustasaurus Bobosaurus Chinchenia Kwangsisaurus Pistosaurus Tanaisosaurus Wangosaurus Yunguisaurus
Plesiosauria	see below↓

Eardasaurus Gallardosaurus Liopleurodon Lorrainosaurus Megalneusaurus UANL-FCT-R2? Peloneustes "Pliosaurus" andrewsi Pliosaurus Simolestes
Brachaucheninae	Acostasaurus Brachauchenius Eiectus Kronosaurus Luskhan Makhaira Megacephalosaurus Monquirasaurus Polyptychodon Sachicasaurus Stenorhynchosaurus

Plesiosauroidea

Eoplesiosaurus Eretmosaurus Franconiasaurus Leurospondylus Plesiopharos Plesiopterys Plesiosaurus Westphaliasaurus
Microcleididae	Hydrorion Lusonectes Microcleidus Occitanosaurus Seeleyosaurus
Cryptoclidia	see below↓

Cryptoclidia

Cryptoclididae

Opallionectes
Colymbosaurinae	Abyssosaurus Colymbosaurus Djupedalia Pantosaurus Spitrasaurus
Cryptoclidinae	Cryptoclidus Kimmerosaurus Ophthalmothule Tatenectes
Muraenosaurinae	Muraenosaurus Picrocleidus Tricleidus? Vinialesaurus

Xenopsaria

Leptocleidia

Hastanectes?
Nichollssaura?

Leptocleididae

Polycotylidae

Palmulasaurinae

Pahasapasaurus?
Palmulasaurus

Occultonectia

Plesiopleurodon
Sulcusuchus

Polycotylinae

Dolichorhynchia	Dolichorhynchops Martinectes Unktaheela

Aphrosaurus Chubutinectes Futabasaurus Fresnosaurus? Hydrotherosaurus? Kawanectes Marambionectes Morenosaurus Tuarangisaurus Vegasaurus Zarafasaura?
Aristonectinae	Alexandronectes Aristonectes Kaiwhekea Morturneria Wunyelfia