EPOW - Ecology Picture of the Week

Massospondylus carinatus, Family Massospondylidae
Zimbabwe, Africa

Explanation:   In the arid mopane woodlands along the Limpopo River in southern Zimbabwe of south Africa occurs this fearsome-looking beast.  It is from times long past when this area was likely more lushly vegetated.

It is a dinosaur called Massospondylus carinatus.  Massospondylus (mass-oh-spon-DIE-lus) means "bulky vertebra," and carinatus comes from the word carinated meaning having a ridge or being shaped like the ridge or keel of a ship, describing one of its features.

(left) The complete skeletal remains of a Massospondylus carinatus. (Click for larger version)

This was a plant-eater from the early Jurassic and Triassic of at least 195 million years ago.  It measured some 5 meters (15 feet) long and was first described from the fossil record by Owen in 1854.

Fossils of Massospondylus carinatus have been found in southern Africa and also possibly in Arizona, USA, and South America, suggesting its ancient life when continents were connected.  

Although the literature states that this beast was a plant-eater (vegetarian), its teeth, claws, large orbit (eye socket), and huge nasal cavity suggest that it may also have been a carrion-feeder or perhaps even an active predator.  Cavities or fossae in the skull may also help it be light and very agile, but how much agility would a plant-eater need? 

The simple, conical teech of Massospondylus carinatus

At this site have been discovered 29 specimens of Massospondylus carinatus over an area of 8 square kilometers (3 square miles or about 2000 acres), an incredible density.  This local density suggests that it may have occurred in herds, which in turn may suggest either an herbivorous or an omnivorous or even carnivorous species.  Large-bodied herbivores found today in Africa, such as Cape Buffalo and zebra, often group into herds to help reduce the chance of predation on any one animal.  However, African carnivores such as African Wild Dogs can also form groups (hunting packs) to more efficiently prey on herbivores. 

One source suggests that over 80 partial skeletons but only 4 skulls of Massospondylus carinatus have been found.  One of these rare skulls is featured in this week's EPOW.  

This species was a Sauropodomorpha (a long-necked plant-eating dinosaur), more precisely a "prosauropod," one of the poorest known groups of dinosaurs. Massospondylus is but one of many synonyms for this beast.  

One of the claws

Information:  See this site for references on Massospondylus, and this site for references on Prosauropoda.