Entomolithus (petrified insect) is an obsolete scientific name for several trilobites, first published by Linnaeus in 1753, before the starting point of zoological nomenclature in a list under the heading "Paradoxus: 3. Entomolithus Monoculi". This is why this first name has no formal status. After the starting point of the zoological nomenclature, the name was published again in 1759, but with a different description. Because scholars incorrectly considered Entomolithus <small>Linnaeus, 1759</small> a junior homonym, it was later replaced by Entomostracites <small>Wahlenberg, 1818</small>. Although the name as published in 1759 was in fact valid, the International Commission on Zoological Nomenclature decided to suppress Entomolithus <small>Linnaeus, 1759</small>, because this name had gone out of use for a very long time.
Species originally assigned to Entomolithus have been renamed.