placoderm
noun
plac·o·derm
ˈpla-kə-ˌdərm 
: any of a class (Placodermi) of extinct chiefly Devonian fishes with an armor of bony plates and primitive jaw structures
Examples of placoderm in a Sentence
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Known as placoderms, these primitive jawed vertebrates came in all shapes and sizes, from small bottom-dwellers to giant filter-feeders.
—
Jack Tamisiea, New York Times, 30 Jan. 2024
As a placoderm, Alienacanthus belonged to the earliest groups of vertebrates to develop complex jaws.
—Jack Tamisiea, New York Times, 30 Jan. 2024
Dunkleosteus, a genus from a class of armored fish called the placoderms, reached greater dimensions and could have easily preyed on early chondrichthyans.
—Joshua Rapp Learn, Discover Magazine, 1 Apr. 2023
Entelgnathus primordialis was an eight-inch-long placoderm — a kind of armored fish — and lived in seas that covered China 419 million years ago.
—Gemma Tarlach, Discover Magazine, 25 Sep. 2013
The arthrodire placoderm fossil from the Gogo Formation in Australia where the 380 million-year-old mineralized heart was discovered.
—Jennifer Ouellette, Ars Technica, 21 Sep. 2022
Enlarge / Reconstruction of a Devonian arthrodire placoderm.
—Jennifer Ouellette, Ars Technica, 21 Sep. 2022
Trinajstic and her team had previously discovered mineralized muscle tissue in these same placoderm fossils.
—Stephanie Pappas, Scientific American, 15 Sep. 2022
From one layer to the next one above, no more trilobites or nightmarish placoderms or dimetrodons—entire animal reigns and ecosystems have vanished.
—Manu Saadia, Ars Technica, 4 Sep. 2017
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Jack Tamisiea, New York Times, 30 Jan. 2024
As a placoderm, Alienacanthus belonged to the earliest groups of vertebrates to develop complex jaws.
—Jack Tamisiea, New York Times, 30 Jan. 2024
Dunkleosteus, a genus from a class of armored fish called the placoderms, reached greater dimensions and could have easily preyed on early chondrichthyans.
—Joshua Rapp Learn, Discover Magazine, 1 Apr. 2023
Entelgnathus primordialis was an eight-inch-long placoderm — a kind of armored fish — and lived in seas that covered China 419 million years ago.
—Gemma Tarlach, Discover Magazine, 25 Sep. 2013
The arthrodire placoderm fossil from the Gogo Formation in Australia where the 380 million-year-old mineralized heart was discovered.
—Jennifer Ouellette, Ars Technica, 21 Sep. 2022
Enlarge / Reconstruction of a Devonian arthrodire placoderm.
—Jennifer Ouellette, Ars Technica, 21 Sep. 2022
Trinajstic and her team had previously discovered mineralized muscle tissue in these same placoderm fossils.
—Stephanie Pappas, Scientific American, 15 Sep. 2022
From one layer to the next one above, no more trilobites or nightmarish placoderms or dimetrodons—entire animal reigns and ecosystems have vanished.
—Manu Saadia, Ars Technica, 4 Sep. 2017
Dictionary Entries Near placoderm
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“Placoderm.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/placoderm. Accessed 22 Dec. 2024.
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