Ceraurus
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Ceraurus |
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Extinct (fossil)
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Ceraurus is a genus of cheirurid trilobite of the middle and, much more rarely, the upper Ordovician. It is commonly found in strata in the lower Great Lakes region. Ceraurus have eleven thoracic segments, long genal and pygidial spines, and very small pygidia. The taxonomy of the genus is very confused, as there are many variations of Ceraurus' eye placement, pustulation, and spine length. "Ceraurus" may, in fact, be at least four genuses: True Ceraurus; Gabriceraurus; Bufoceraurus; and Leviceraurus. Ceraurus is quite common in the Ordovician of upstate New York, south-central and south-eastern Ontario, and the St. Lawrence Valley in Quebec, as well as the Canadian arctic. Ceraurus and its similar genuses range in size from less than a quarter inch to well over five inches. Similar genus of trilobites occur in the Ordovician outcrops of the Wolchow River, near St. Petersburg, Russia.
[edit] Reference
Ludvigsen, Rolf, Fossils of Ontario: Part I: The Trilobites. Toronto: Royal Ontario Museum, 1983.