Symphysops
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| Symphysops Temporal range: | |
|---|---|
 | |
| probably Symphysops stevaninae, cephalon 24mm long, lateral view, found near Alnif, Morocco, from the Ordovician | |
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Clade: | †Artiopoda |
| Class: | †Trilobita |
| Order: | †Asaphida |
| Family: | †Cyclopygidae |
| Genus: | †Symphysops Raymond, 1925 |
| Species | |
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See text | |
Symphysops is a genus of trilobites of average size, belonging to the Cyclopygidae family. It had a cosmopolitan distribution and lived from the Middle to the Upper Ordovician (Llanvirn to Ashgill). It has been found in Canada (Quebec and Newfoundland), China, the Czech Republic (Bohemia), Iran, Ireland, Kazakhstan, Poland, Morocco, Spain, Scotland and Wales.[1] The name Symphysops refers to the fused eyes, common to the species of this genus. Some (sub)species of the cyclopygid genera Cyclopyge and Pricyclopyge share this character, but Symphysops uniquely combines the merged eye with a frontal thorn on the head and the "lower eyelid".
Symphysops is characterized by large eyes that merge at the front of the headshield (or cephalon) to form what looks like a visor with at the back a wide free cheek. The remainder of the cephalon is filled by the glabella, which in most species extends into a forward pointing thorn at its frontal tip. The occipital ring cannot be distinguish from the rest of the glabella, which has two pair of transverse furrows, the rear pair distinct, and the frontal pair very shallow. The thorax consists of six segments, the frontal segment carrying backward directed pleural spines.[2]
