21145 - Premium Grade Soft Bodied Xiphosurid (Horseshoe Crab Ancestor) Lower Ordovician Paralejurus but not quite as large

but not quite as large as Spinosaurus

The dentary terminates abruptly in front of the first tooth

Michael Festnacht suggested it was more similar to Anhanguera due to the wide end of the snout

Otarion sp: Fossilworks (Paleobiology Database)

21145 - Premium Grade Soft Bodied Xiphosurid (Horseshoe Crab Ancestor) Lower Ordovician Paralejurus but not quite as largeXiphosurans 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