21183 - Premium Grade Soft Bodied Xiphosurid (Horseshoe Crab Ancestor) Lower Ordovician Mimagoniatites Publications of the Eternal River

Publications of the Eternal River Museum of Natural History

an emerging germ replacement tooth

Mass (g): 2553 kg

†Onnia sp

• Silurian of Canada ( Northwest Territories

21183 - Premium Grade Soft Bodied Xiphosurid (Horseshoe Crab Ancestor) Lower Ordovician Mimagoniatites Publications of the Eternal RiverXiphosurans are an order of arthropods related to arachnids, or, according to one recent study, actually arachnids. They are sometimes called horseshoe crabs (a name applied more specifically to the only extant family, Limulidae). They first appeared in the Tremadocian (Lower Ordovician) from Fezouata Fm in South Morocco. Currently, there are only four living species. They are members of the order Xiphosura, which contains two suborders, Xiphosurida