fossil marine animal genera Linnaeus, 1758 - animals Phylum Arthropoda Siebold, 1848 - arthropods Class Merostomata Dana, 1852 - horseshoe crabs see Class Xiphosura Latreille, 1802 ?Order †Aglaspida (Walcott, 1911), nom. illeg. see Order Aglaspidida Walcott, 1911