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Barrandeocerids are mostly coiled nautiloid cephalopods comprising some six families, that lived from the Middle Ordovician to the Middle Devonian, a span of around 100 million years. Derivation is from within the Tarphyceratidae.

Shells are variably coiled, some planar, others trochoidal. Siphuncles have thin-walled connecting rings, which distinguishes them from the tarphycerids in which connecting rings are thick-walled and layered.

The following six families, starting with the oldest, have been described.
Barrandeoceratidae M Ord - M Dev
Plectoceratidae: M -U Ord 
Aspidoceratidae: M-U Ord 
Uranoceratidae:  U Ord - M Sil.
Lechritrochoceratidae: M -U  Sil 
Nephriticeratidae: L -M Dev 

The last of the barrandeocerids became extinct near the end of the Middle Devonian, apparently without giving rise to any progeny.

References
Walter C. Sweet, 1964. Nautilodea - Barrandeocerida. Treatise on Invertebrate Paleontology. Part K   (K368 -K382)
Mary Wade, 1988. Nautiloids and their descendants: cephalopod classification in 1986. New Mexico Bureau of Mines & Mineral Resources Memoir 44

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