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  2. Trilobite - Wikipedia

    en.wikipedia.org/wiki/Trilobite

    Exactly why the trilobites became extinct is not clear; with repeated extinction events (often followed by apparent recovery) throughout the trilobite fossil record, a combination of causes is likely. After the extinction event at the end of the Devonian period, what trilobite diversity remained was bottlenecked into the order Proetida.

  3. Angelina (trilobite) - Wikipedia

    en.wikipedia.org/wiki/Angelina_(trilobite)

    Angelina Salter, 1859, [1] is a genus of ptychopariid trilobite belonging to the Family Olenidae, Suborder olenina. It lived during the Tremadocian Stage, lowermost of the two standard worldwide divisions forming the Lower Ordovician Series and lowest of the seven stages within the Ordovician System. It encompasses all rocks formed during ...

  4. Late Ordovician mass extinction - Wikipedia

    en.wikipedia.org/wiki/Late_Ordovician_mass...

    Trilobites were hit hard by both phases of the extinction, with about 70% of genera and 50% of families going extinct between the Katian and Silurian. The extinction disproportionately affected deep water species and groups with fully planktonic larvae or adults.

  5. Trilobites were arthropods, like modern insects, spiders, millipedes and crustaceans, and they evolved into a wide range of shapes and sizes before going extinct around 252 million years ago. Most ...

  6. Ptychopariida - Wikipedia

    en.wikipedia.org/wiki/Ptychopariida

    Ptychopariida is a large, heterogeneous order of trilobite containing some of the most primitive species known. The earliest species occurred in the second half of the Lower Cambrian, and the last species did not survive the Ordovician–Silurian extinction event. Asaphiscus wheeleri, a Cambrian trilobite of the Superfamily Ptychoparioidea

  7. Nevadella - Wikipedia

    en.wikipedia.org/wiki/Nevadella

    Nevadella is an extinct genus of trilobites, fossil marine arthropods, with species of average size (about 5 centimetres or 2.0 inches long). It lived during the late Atdabanian stage, which lasted from 530 to 524 million years ago during the early part of the Cambrian Period .

  8. Animals of Devonian Michigan - Wikipedia

    en.wikipedia.org/wiki/Animals_of_Devonian_Michigan

    Trilobites are an extinct group of ancient marine Arthropods that lived from the early Cambrian period (roughly 541 mya) to the great Permian extinction (252 mya). The name trilobite refers to the three lobes every trilobite body has: the axial lobe, running down the center of the animal, and the pleural lobes, located on either side of the ...

  9. Paraphillipsia - Wikipedia

    en.wikipedia.org/wiki/Paraphillipsia

    Paraphillipsia is a genus of proetid trilobite in the family Phillipsiidae. [1] [2] It is notable for being one of the last trilobites to go extinct during the Permian–Triassic extinction event. [3]