Description
Synziphosurine
Early Ordovician (Arenigian)
Upper Fezouata Formation
Zagora, Draa Valley, Morocco
33mm positive with appendages on 90mm x 60mm slab.
This is the first known occurrence in Africa and the earliest known occurrence of synziphosurines anywhere. They are better known from the Early Silurian to Early Carboniferous of North America and Europe.
A synziphosurine is a member of a suborder of arthropods, Synziphosurina, considered to be stem-group xiphosurans. In other words, based on current understanding, they may not be directly ancestral to xiphosurans (horseshoe crabs) but they are a side group more closely related to their ancestors than to other groups.
Nice contrast between the fossil and the matrix; nice specimen too.
What did it look like in life? Take a look at this amazing video of a 3D scan of a similar, younger specimen from the Silurian:
