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Entomaspis

Entomaspis is an extinct genus of harpetid trilobite from Upper Cambrian to Early Ordovician marine strata of the United States. Species are typified by their proportionally large, vaulted, croissant-shaped or bonnet-shaped cephalons that have the cheeks freed to become elongated, curved librigenial spines, and by their comparatively large, crescent-shaped eyes (in comparison with other eyed harpetids).