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Orthothecida

Orthothecida
Temporal range: Early Cambrian – Early Devonian
Scientific classification
Kingdom: Animalia
Informal group: Lophophorata
Class: Hyolitha
Order: Orthothecida
Family: Orthothecidae
Marek, 1966
Genera

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The orthothecids are one of the two hyolith orders.


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Wikipedia

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