Metaspriggina
Metaspriggina | ||||||||||||
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An illustration by Metaspriggina walcotti |
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Temporal occurrence | ||||||||||||
Middle Cambrian | ||||||||||||
510 million years | ||||||||||||
Locations | ||||||||||||
Systematics | ||||||||||||
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Scientific name | ||||||||||||
Metaspriggina | ||||||||||||
Simonetta & Insom , 1993 | ||||||||||||
species | ||||||||||||
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Metaspriggina is a genus of extinct chordates . At the moment only the type species Metaspriggina walcotti is known, of which two specimens from the Burgess slate from the Middle Cambrian were brought to light.
description
Metaspriggina walcotti had an eel-like elongated body, an elongated skull base and a long, triangular, laterally flattened trunk end. The animals were about 7 cm long. The body is criss-crossed with V-shaped elements that are reminiscent of the myomers in the trunk muscles of the lancet fish . One of the two objects can be seen in the skull with eyes. At the rear end the animals had a wide fin edge . The animals probably moved around freely swimming.
Systematics
The fossils were discovered by Charles Walcott , but they were not examined until 1979 by Simon Conway Morris . A first description was provided by Simonetta and Insom in 1993. Initially, one of the two fossils was ascribed to the genus Spriggina , which appeared in the Ediacarian , i.e. before the Cambrian. In 1998, however, this thesis was refuted by Janvier. Both fossils are regarded as belonging to the same species and assigned to the chordates.
literature
- S. Conway Morris: The Burgess Shale (Middle Cambrian) fauna . Annual Review of Ecology and Systematics, 10, 1, pp. 327-349, 1979
- S. Conway Morris: A redescription of a rare chordate, Metaspriggina walcotti Simonetta and Insom, from the Burgess Shale (Middle Cambrian), British Columbia, Canada . Journal of Paleontology, 82, 2, 424-430, 2008
- P. Janvier: Les vertébrés avant le Silurien . GeoBios, 30, pp. 931-950, 1998
- AM Simonetta, E. Insom: New animals from the Burgess Shale (Middle Cambrian) and their possible significance for the understanding of the Bilateria . Bolletino di Zoologia, 60, 1, pp. 97-107, 1993
- MP Smith, IJ Sansom, and KD Cochrane: The Cambrian origin of vertebrates . In: PE Ahlberg (ed.), Major Events in Early Vertebrate Evolution: Palaeontology, Phylogeny, Genetics and Development . Pp. 67-84, Taylor and Francis, London 2001.
Individual evidence
- ↑ AM Simonetta and E. Insom: New animals from the Burgess Shale (Middle Cambrian) and their possible significance for the understanding of the Bilateria . Bolletino di Zoologia, 60, 1, pp. 97-107, 1993
- ^ Conway Morris, Simon: A Redescription of a Rare Chordate , Metaspriggina Walcotti Simonetta and Insom, from the Burgess Shale (Middle Cambrian), British Columbia, Canada . In: Journal of Paleontology . 82, No. 2, 2008, p. 424. doi : 10.1666 / 06-130.1 .
- ↑ a b Picture and description of Metaspriggina walcotti at the Royal Ontario Museum