C. canadensis was described in 1881 from material found in Miguasha, Canada that dated back to the middle Frasnian stage of the Late Devonian. Two species, C. gracilis and C. gaugeri, have been found from Germany and Belarus in deposits that are of Givetian age. They were first described in 1973 from scale material that is now of questionable validity.
The fossil record of C. canadensis dates back to 1881, with remains found in Miguasha, Canada, during the middle Frasnian stage of the Late Devonian period. Later discoveries of related species, such as C. gracilis and C. gaugeri, were made in Germany and Belarus, initially described in 1973 from questionable scale samples.