Trilobite, any member of a group of extinct fossil arthropods easily recognized by their distinctive three-lobed, three-segmented form. Trilobites, exclusively marine animals, first appeared at the beginning of the Cambrian Period, about 542 million years ago, when they dominated the seas. Although they became less abundant in succeeding geologic periods, a few forms persisted into the Permian Period, which ended about 251 million years ago.
Asaphus kowalewskii (LAWROW, 1856)Product no.: W3-4Period: Middler Ordovician |
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Homotelus bromidensis (ESKER)Product no.: 3075Period: Simpson Group, Late Ordovician |
Salterolithus carataci (MURCHISON, 1839)Product no.: M1-5Period: Cardic, Late Ordovician |
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Parapathycheilus cf. gallicus (DEAN)Product no.: G1-1Period: Arenigian, Early Ordovician |
Ectillaenus caecus (HOLM, 1886)Product no.: O7-11Period: Kullsberg Limestone, Katian, Late Ordovician |
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Asaphus cf. expansus (WAHLENBERG, 1821)Product no.: O7-9Period: Ordovician |
Salterolithus carataci (MURCHISON, 1839)Product no.: 1235Period: Cardic, Late Ordovician |
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