Dino of the Week: Spinostropheus

Type Species: Spinostropheus gautieri

Classification: Dinosauria – Saurischia – Theropoda – Ceratosauria 

Time Period: Middle Jurassic

Location: Africa (Niger) 

Diet: Carnivore 

In the Middle Jurassic, Saharan Africa was a lush mosaic of woodlands, rivers, and lakes – and the lithe, agile predator Spinostropheus hunted among the forests and waterways. It was by no means the largest predator in its environment; that title went to its contemporary Afrovenator, which grew to about thirty feet in length. Spinostropheus’ length is hotly debated: in 2010 it was estimated at around thirteen feet in length (about half that of Afrovenator); in 2012 the length was pushed up to twenty feet; and in 2016 it was estimated to be around twenty-eight feet in length, on par with its contemporary. Most scientists tend towards the original estimate, picturing Spinostropheus as a smaller predator in its environment. 

Its prey is unknown, as the Saharan fossil record for this period consists of much larger sauropods and theropods. The fossilized scutes of an unnamed early thyreophoran have been discovered in the region, and so early armored ornithischians resembling Scutellosaurus or Scelidosaurus – both of which were present nearby in North America just a handful of million years earlier – seem to have called the Sahara home. Spinostropheus, being quick-footed, likely preyed on these agile early ornithischians; it may also have preyed on smaller terrestrial creatures like mammals, lizards, and perhaps even crocodylomorphs. Spinostropheus is considered one of the earliest ceratosaurs (the lineage that would lead to the infamous Ceratosaurus in the Late Jurassic), and it resembled an earlier, smaller version of the Late Jurassic Elaphrosaurus.