- Telling the Evolutionary Time: Molecular Clocks and the Fossil Record (Systematics Association Special Volume) by Philip C J Donoghue and M. Paul Smith (page 227)
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| Procephalaspis | |
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| Procephalaspis Temporal range: Silurian
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| Scientific classification | |
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| Genus: | †Procephalaspis
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Procephalaspis is an extinct genus of jawless fish.