In Episode 139 we got a chance to speak with Danny Barta, a PhD candidate in Comparative Biology at the American Museum of Natural History (AMNH) in New York City. We talk to him about “The Titanosaur” exhibit at AMNH and details about when it was found in Argentina.

Episode 139 is also about Bahariasaurus, a giant Egyptian theropod that likely lived at the same time as Spinosaurus.

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In this episode, we discuss:

In dinosaur news:

The dinosaur of the day: Bahariasaurus

Name means Bahariya lizard

Type species is Bahariasaurus ingens

Described in 1934 by Ernst Stromer

Holotype consisted of two dorsal vertebrae, neural arch, sacral vertebrae, rig fragment, pubes and ischium fragment

Type specimen was destroyed in WWII

Not clear how to classifiy it, and it’s been assigned to a few theropod groups

In 1995, Oliver Rauhut compared Carcharodontosaurus and Bahariasaurus to ceratosaurs, torvosauridae, tyrannosaurida, coeulrosauria, and allosauroida, based on data Stromer published in 1931, 1934, and 1936. Stromer named a new family in 1031, Carcharodontosauridae, for Carcharodontosaurus. He thought both Carcharodontosaurus and Bahariasaurus were theropods but were not closely related. In 1960 Lapparent classified Bahariasaurus as a megalosaurid, and others agreed over the years, though in 1990 Molnar and others said it was Carnosauria incertae sedis (uncertain placement) and that Carnosauria consisted of Allosauridae and Tyrannosauridae). In 1991 Bonaparte said it was more closely related to Abelisauridae and Noasauridae. But Rauhut thought that Carcharodontosaurus and Bahariasaurus were closely related because they had pleurocoels in their caudal vertebrae (hollow depressions to help decrease weight). He referred both of them to Allosauroidea.

In 2000, Chure suggested it was Tyrannosauroidea

Potentially synonymous with Deltadromeus (theropod that lived around the same time in North Africa and has been found in the same formations), but too hard to tell since Bahariasaurus remains were destroyed

If it is synonymous, it would have been large (estimated 26 ft or 8 m long)

Need more specimens to know for sure, and to classify it

In 2016, it was suggested that Aoniraptor, Bahariasaurus, and Deltadromeus could possibly be a not well known clade of megaraptoran tyrannosaroids

Large theropod that lived in the Cretaceous in what is now Egypt

About the same size as Tyrannosaurus and Carcharodontosaurus (maybe)

Probably lived in the same time and place as Spinosaurus and Carcharodontosaurus

Fun Fact:

Spiders aren’t insects, they’re arachnids

Spiders were walking around on land before dinosaurs evolved. But the first orb weaving spiders (spiders that make webs) didn’t show up until much later. The oldest direct evidence that we have for spider webs are webs trapped in amber from the early cretaceous

Based on estimations from other specimens and genetics it’s believed that the first orb weavers evolved in the Jurassic

Lots of flying insects evolved in the early cretaceous

May have led to the rise in spider diversity that we see then

In other words, T. rex and Triceratops would have walked through a lot of spider webs, but Stegosaurus, Apatosaurus, and Allosaurus, probably didn’t have to deal with many spider webs (if any)

And poor rex with his short arms had no good way to get spider webs off its face

Interview:

Transcript coming soon…