Paleontologists Discover Oldest Known Titanosaur: Ninjatitan zapatai
Ninjatitan zapatai lived approximately 140 million years ago (Early Cretaceous period) in what is now Patagonia, Argentina.
Ninjatitan zapatai belongs to Titanosauria, a diverse group of sauropod (long-necked plant-eating) dinosaurs.
This group includes species ranging from the largest known terrestrial vertebrates to ‘dwarfs’ no bigger than elephants.
“During evolutionary history, sauropods had different moments, different pulses of gigantism, which were not only related to the group of titanosaurs,” said Dr. Pablo Ariel Gallina, a paleontologist at the Fundación Azara in Maimonides University and CONICET.
“There were large animals towards the end of the Jurassic period, such as Apatosaurus and Brachiosaurus. And, already in the line of titanosaurs, the pulse with the largest giants occurs towards the middle of the Cretaceous period, with species such as Patagotitan, Argentinosaurus or Notocolossus.”
Ninjatitan zapatai was about 20 m (66 feet) in length, and had a long neck and tail.
“The main importance of Ninjatitan zapatai, beyond the fact that it is a new species of titanosaur, is that it is the earliest record worldwide for this group,” Dr. Gallina said.
“This discovery is also very important for the knowledge of the evolutionary history of sauropods, because the fossil records of the Early Cretaceous period, in around 140 million years ago, are really very scarce throughout the world.”
The 140-million-year-old postcranial remains of Ninjatitan zapatai were discovered in the Bajada Colorada Formation in Neuquén province, Patagonia region, Argentina.
“The presence of a basal titanosaurian sauropod in the lowermost Cretaceous of Patagonia supports the hypothesis that the group was established in the southern hemisphere and reinforces the idea of a Gondwanan origin for Titanosauria,” the researchers said.
The discovery of Ninjatitan zapatai is described in a paper in the journal Ameghiniana.
P.A. Gallina et al. 2021 The earliest known titanosaur sauropod dinosaur. Ameghiniana 58 (1): 35-51; doi: 10.5710/AMGH.20.08.2020.3376