Episode 327 is all about Zigongosaurus, A mamenchisaurid that was about 50 ft (15 m) long, but may be an Omeisaurus, Mamenchisaurus, or even a nomen nudum.

We also interview Rebecca Slater, Art Director and one of original creators of Path of Titans. The dinosaur MMO survival game where all players take on the role of a dinosaur. You can follow their updates or get the game at https://pathoftitans.com/

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In this episode, we discuss:

News:

• Over 3,500 hours have gone into the massive Utahraptor block to date, uncovering over a dozen individuals so far source
• A Bohaiornis specimen appears to have gemstones that formed in its abdomen during fossilization source
• In Pennsylvania, the Philadelphia Zoo is getting animatronic dinosaurs source
• The unreleased Nintendo 64 game Dinosaur Planet is now available on the Internet Archive source
• After an update to the game No Man’s Sky, several sauropod-like creatures have been hatched source

The dinosaur of the day: Zigongosaurus

• Mamenchisaurid sauropod that lived in the Middle Jurassic in Zigong, Sichuan, China (Shaximiao Formation)
• Looks like a typical sauropod
• Large, quadrupedal, and herbivorous
• Had a long neck
• Estimated to be about 50 ft (15 m) long
• Different from Zizhongosaurus, a basal sauropod that lived in the Middle Jurassic in what is now China)
• Type species is Zigongosaurus fuxiensis
• Genus name means “Zigong lizard”
• Named in 1976 by Hou, Zhao, and Chao
• Based on CV 00261, and includes a partial mandible, maxilla, and bone from the braincase area
• Other specimens referred to Zigongosaurus (at least four specimens), and included dorsal vertebrae, pubis, and ischium
• Authors thought it looked like Omeisaurus, but the vertebrae was different enough to be its own genus (had weak bifurcated, or split, neural spines on the vertebrae)
• Debate over whether or not it’s a valid genus
• Has been synonymized with Omeisaurus and Mamenchisaurus
• In 1983, Dong, Zhou, and Zhang wrote a book, Dinosaurs from the Jurassic of Sichuan, and said Zigongosaurus fuxiensis was Omeisaurus fuxiensis
• In the book, they said there were time constraints around preparing, studying, and putting Zigongosaurus on display, so not all the data could be analyzed, and that led to the material that was analyzed being named Zigongosaurus fuxiensis
• Their analysis led them to reclassify Zigongosaurus as Omeisaurus, based on its stratigraphic position (same environment where other Omeisaurus was found)
• Omeisaurus was named in 1939 by Young and others, however the type specimen was fragmentary and a lot of it lost in transport during WWII, so Dong, Zhou, and Zhang selected a neotype in 1983
• In 1996 Zhang and Chen suggested it was Mamenchisaurus fuxiensis, and said it came from a strata between where Omeisaurus and Mamenchisaurus was found, but that it looked more like Mamenchisaurus
• In 1997 Li and Cai said it was a nomen nudum
• In 1999, Valérie Martin-Rolland found Zigongosaurus to be valid
• In 2019, Wang and others found it to be undiagnostic
• The paratype for Zigongosaurus fuxiensis was a maxilla with three teeth, and was thought to possibly from be a juvenile

Fun Fact: Creating a dinosaur topiary is probably easier than you think.

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