Deinocheirus > Spinosaurus

There’s a new giant, sail-backed, piscivorous theropod in town.

Just a month after Ibrahim et al. (2014) revealed their new interpretation of Spinosaurus aegypticus, Lee et al. have done one better: they've published a description of Deinocheirus mirificus, one of the most mysterious dinosaurs ever found. For those not keeping score at home, Deinocheirus was discovered in 1965 during a Polish-Mongolian expedition into the southern Gobi Desert. Unfortunately, all that was found was a pair of enormous arms—indelibly seared into the minds of every man, woman, and child who opened a dinosaur book over the next forty years. It was pretty easy to see that Deinocheirus was an ornithomimid, but it must have been absolutely enormous. It wasn't until 2006 and 2009 that more skeletal material was discovered—both in the field and in a private collection. For more on this, Ed Yong and Brian Switek have fascinating write-ups about the discovery and its history.

Spinosaurus-world Problems

Spinosaurus aegypticus, lord of the Kem Kem river system.

September 12th saw the publication of Ibrahim et al.’s new reconstruction of Spinosaurus aegypticus, surely one of the most famous and mysterious of all dinosaurs. The authors designate a neotype, assign a bunch of previously indeterminate material to S. aegypticus, synonymize “Spinosaurus maroccanus” and “Sigilmassassaurus brevicollis” into S. aegypticus, and offer up a bizarre interpretation of the whole animal. No longer confined to wading in rivers and snatching up fish a la Suchomimus, Spinosaurus is now a proper semi-aquatic dinosaur that the authors compare to early whales. Aside from being published in Science, National Geographic appears to be paying the bills and fabricated a massive skeletal reconstruction and life-size model. As can be expected, there was much media fanfare surrounding the publication and public unveiling.