21161 - Premium Grade Soft Bodied Xiphosurid (Horseshoe Crab Ancestor) Lower Ordovician Shark dunklei there were two to

dunklei there were two to five barbs on each tooth

It is still preserved included in part of the sandy-gravel sediment that is cemented and mineralized to its surface

shallow subtidal (5)

England (Lingham−Soliar1993)

Rare rooted specimen

21161 - Premium Grade Soft Bodied Xiphosurid (Horseshoe Crab Ancestor) Lower Ordovician Shark dunklei there were two toXiphosurans 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