Kingdom Animalia Class †Hyolitha | Informal group Lophophorata Rank Order | |
Family †Orthothecidae
Marek, 1966 Similar Hyolitha, Conulariida, Rostroconchia, Orthida, Asaphida | ||
The orthothecids are one of the two hyolith orders.
References
Orthothecida Wikipedia(Text) CC BY-SA