Large Aturia Nautiloid Survivor Fossil

 Description: This fine Nautiloid is an Aturia from the far Western Sahara of Morocco which is prepped to self-display on its flattened matrix base. This allows you the opportunity to view this fine, robust specimen from all aspects. It has been polished to bring out the fine details. The complex suturing pattern distinguishes these cephalopods from the ammonites (I have posted it with the ammonites as they are close relatives). Indeed the suture is one of the most complex for all Nautiloids. The Nautilida have a rich evolutionary history which began in the early Devonian. The order suffered a drastic decline in the late Devonian, only to have an extensive radiation in the Carboniferous. They suffered less than some other orders at the end of the Permian, and did better than the ammonites by surviving the Cretaceous extinction, leaving one descendant, the modern-day Nautilus. Why did the Nautilida survive the end-Cretaceous catastrophe while all Ammonites perished? The Ammonites were more restricted in distribution, and were more often found in shallower environments that the Nautilida. While there is some evidence that the may have persisted for some 100,000 years after the meteor stuck, that is the last of them. The Aturidae held out until the Miocene, while two species of Nautiloids exist today as deep water inhabitants.