Excalibosaurus (meaning "Excalibur's lizard") is a monotypic genus of marine prehistoric reptiles (ichthyosaurs) that lived during the Sinemurian stage (approximately 196.5 ± 2 Ma to 190.8 ± 1.0 Ma (million years ago)) of the Early Jurassic period in what is now England. It is characterized by the extreme elongation of the rostrum, with the lower jaw about three-quarters the length of the upper jaw, giving the animal a swordfish-like look. The only known species is Excalibosaurus costini.
This relatively rare animal is known from two skeletons. The holotype, discovered in 1984 near a beach on the Somerset coast, consists of the skull, forefin, part of the pectoral girdle and some vertebrae and ribs. It has been described in 1986 by Christopher McGowan.[2] The fossil is hosted in the Bristol City Museum and Art Gallery. The second specimen is an almost complete skeleton collected in the same area in 1996, and was purchased by the Royal Ontario Museum. It was described again by McGowan in 2003.[3]
Descriptionedit
The holotype specimen has a skull length of 78.5 cm (2 ft 6.9 in), while the largest specimen has a skull length of 1.54 m (5 ft 1 in).[3] The larger specimen has a total length of 6.528 metres (21.42 ft).[4]
Classificationedit
Excalibosaurus is related to two other genera of ichthyosaurs, Leptonectes from the Rhaetian (Late Triassic) to the Sinemurian (Early Jurassic) of England and Eurhinosaurus from the Toarcian (Early Jurassic) of Germany. The three genera are grouped in the family Leptonectidae.[5][6][3] It was once thought that Excalibosaurus was a junior synonym of Eurhinosaurus,[7] but the description of the 1996 specimen show many morphological differences such as the shape of the forefin (much shorter and broader in Excalibosaurus), the slender shape of the body, that clearly differentiate the two genera.[3]
^"Excalibosaurus at Fossilworks". Paleobiology Database. Fossilworks. Retrieved 17 December 2021.
^McGowan, C. (1986). "A putative ancestor for the swordfish-like ichthyosaur Eurhinosaurus". Nature. 322 (6078): 454–456. Bibcode:1986Natur.322..454M. doi:10.1038/322454a0. S2CID 4255439.
^ abcdMcGowan, C. (2003). "A new Specimen of Excalibosaurus from the English Lower Jurassic". Journal of Vertebrate Paleontology. 23 (4): 950–956. doi:10.1671/1860-20. S2CID 129236415.
^Martin, J.E.; Vincent, P.; Suan, G.; Sharpe, T.; Hodges, P.; William, M.; Howells, C.; Fischer, V. (2015). "A Mysterious Giant Ichthyosaur from the Lowermost Jurassic of Wales". Acta Palaeontologica Polonica. 60 (4). Institute of Paleobiology, Polish Academy of Sciences: 837–842. doi:10.4202/app.00062.2014. S2CID 13714078. Supplementary Information
^Maisch, M. W. (1998). "A new ichthyosaurian genus from the Posidonia Shale (Lower Toarcian, Jurassic) of Holzmaden, SW-Germany, with comments on the phylogeny of post-Triassic ichthyosaurs". Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen. 209 (1): 47–78. doi:10.1127/njgpa/209/1998/47.
^Motani, R. (1999). "Phylogeny of the Ichthyopterygia". Journal of Vertebrate Paleontology. 19 (3): 473–496. doi:10.1080/02724634.1999.10011160.
^Michael W. Maisch & Andreas T. Matzke (2000). "The Ichthyosauria". Stuttgarter Beiträge zur Naturkunde. Serie B. 298: 1–159.
January 01, 1970
excalibosaurus, meaning, excalibur, lizard, monotypic, genus, marine, prehistoric, reptiles, ichthyosaurs, that, lived, during, sinemurian, stage, approximately, million, years, early, jurassic, period, what, england, characterized, extreme, elongation, rostru. Excalibosaurus meaning Excalibur s lizard is a monotypic genus of marine prehistoric reptiles ichthyosaurs that lived during the Sinemurian stage approximately 196 5 2 Ma to 190 8 1 0 Ma million years ago of the Early Jurassic period in what is now England It is characterized by the extreme elongation of the rostrum with the lower jaw about three quarters the length of the upper jaw giving the animal a swordfish like look The only known species is Excalibosaurus costini ExcalibosaurusTemporal range Early Jurassic 196 5 190 8 Ma 1 PreꞒ Ꞓ O S D C P T J K Pg N Fossil Royal Ontario Museum Scientific classification Kingdom Animalia Phylum Chordata Class Sauropsida Order Ichthyosauria Family Leptonectidae Genus ExcalibosaurusMcGowan 1986 Binomial name Excalibosaurus costiniMcGowan 1986 Contents 1 History of research 2 Description 3 Classification 4 See also 5 ReferencesHistory of research edit nbsp Excalibosaurus costini This relatively rare animal is known from two skeletons The holotype discovered in 1984 near a beach on the Somerset coast consists of the skull forefin part of the pectoral girdle and some vertebrae and ribs It has been described in 1986 by Christopher McGowan 2 The fossil is hosted in the Bristol City Museum and Art Gallery The second specimen is an almost complete skeleton collected in the same area in 1996 and was purchased by the Royal Ontario Museum It was described again by McGowan in 2003 3 Description editThe holotype specimen has a skull length of 78 5 cm 2 ft 6 9 in while the largest specimen has a skull length of 1 54 m 5 ft 1 in 3 The larger specimen has a total length of 6 528 metres 21 42 ft 4 Classification editExcalibosaurus is related to two other genera of ichthyosaurs Leptonectes from the Rhaetian Late Triassic to the Sinemurian Early Jurassic of England and Eurhinosaurus from the Toarcian Early Jurassic of Germany The three genera are grouped in the family Leptonectidae 5 6 3 It was once thought that Excalibosaurus was a junior synonym of Eurhinosaurus 7 but the description of the 1996 specimen show many morphological differences such as the shape of the forefin much shorter and broader in Excalibosaurus the slender shape of the body that clearly differentiate the two genera 3 See also edit nbsp Paleontology portal List of ichthyosaurs Timeline of ichthyosaur researchReferences edit Excalibosaurus at Fossilworks Paleobiology Database Fossilworks Retrieved 17 December 2021 McGowan C 1986 A putative ancestor for the swordfish like ichthyosaur Eurhinosaurus Nature 322 6078 454 456 Bibcode 1986Natur 322 454M doi 10 1038 322454a0 S2CID 4255439 a b c d McGowan C 2003 A new Specimen of Excalibosaurus from the English Lower Jurassic Journal of Vertebrate Paleontology 23 4 950 956 doi 10 1671 1860 20 S2CID 129236415 Martin J E Vincent P Suan G Sharpe T Hodges P William M Howells C Fischer V 2015 A Mysterious Giant Ichthyosaur from the Lowermost Jurassic of Wales Acta Palaeontologica Polonica 60 4 Institute of Paleobiology Polish Academy of Sciences 837 842 doi 10 4202 app 00062 2014 S2CID 13714078 Supplementary Information Maisch M W 1998 A new ichthyosaurian genus from the Posidonia Shale Lower Toarcian Jurassic of Holzmaden SW Germany with comments on the phylogeny of post Triassic ichthyosaurs Neues Jahrbuch fur Geologie und Palaontologie Abhandlungen 209 1 47 78 doi 10 1127 njgpa 209 1998 47 Motani R 1999 Phylogeny of the Ichthyopterygia Journal of Vertebrate Paleontology 19 3 473 496 doi 10 1080 02724634 1999 10011160 Michael W Maisch amp Andreas T Matzke 2000 The Ichthyosauria Stuttgarter Beitrage zur Naturkunde Serie B 298 1 159 Retrieved from https en wikipedia org w index php title Excalibosaurus amp oldid 1171989756, wikipedia, wiki, book, books, library,
