Terebratulida

lamp shell

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July 14, 2026

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Terebratulida are a type of brachiopod, also known as lamp shells. These are marine animals with two shells, similar in appearance to bivalve mollusks like clams. However, brachiopods are a distinct phylum. Terebratulids are characterized by their shells, which are typically smooth and often have a distinctive loop-shaped internal support for their lophophore, a feeding organ.123

While many brachiopods are extinct, some terebratulid species are still alive today. The genus Tropidoleptus, for example, is an extinct brachiopod found only in Devonian Period rocks, making it a useful index fossil for correlating rock layers.4

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lamp shells
Annotated classification
Order TerebratulidaPedicle functional, cyrtomatodont teeth; lophophore supported wholly or in part by a calcareous loop, short or long and free or attached to a median septum; more than 300 genera; Early Devonian to Holocene.The classes Articulata and Inarticulata were first proposed by…
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Order TerebratulidaPedicle functional, cyrtomatodont teeth; lophophore supported wholly or in part by a calcareous loop, short or long and free or attached to a median septum; more than 300 genera; Early Devonian to Holocene.The classes Articulata and Inarticulata were first proposed by…
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