Macronaria primarily includes brachiosaurs, titanosaurs and any sauropod associated with them.
The name Macronaria means 'large nostrils' (from Greek makros 'big' + Latin nares 'nostrils'), in reference to the large nasal openings high on the head that probably supported fleshy resonating chambers. Macronaria also contains some of the most of the longest, tallest and most massive dinosaurs of all time.
Brachiosaurs: The Brachiosaurs were Macronarians that had an arch of bone in their nostrils, and unlike those seen in Jurassic Park, they probably couldn't rear up on their back legs (their hind legs were too short for this - the opposite compared to Diplodocoids).
Brachiosaurs first began in the middle Jurassic period and ended in the middle Cretaceous period, but three vertebra from Mexico may suggest they lived to the end.
Brachiosaurs have been found in all northern hemisphere continents and Africa.
Titanosaurs: The Titanosaurs are the other major clade of Macronaria that are recognized in some species as having body armor. This armor is comprised of dome-shaped scutes. Titanosaurs are found on more continents than any other sauropod, except Antarctica (although researchers are on alert for any that may get discovered).
Titanosaurs started in the late Jurassic period and survived to the end of the Cretaceous (and are the only Sauropods known to have survived this long).
Other Macronarians: These are the sauropods that are related to Brachiosaurs and titanosaurs, but are not classed as either group, such as Camarasaurus.
In Walking with... seriesEditBrachiosaurus was featured in this episode. It was a relatively minor character, that appeared as a group of juvenile Diplodocus were searching for their kind. Brachiosaurus didn't interact with them - it was only searching for trees to graze. Argentinosaurus was the main focus of this episode. Land of Giants depicted this dinosaur from death (a solitary skeleton, found by Nigel Marven early in the episode) to youth (a solitary juvenile) to adulthood (living in a large herd and being hunted by Giganotosaurus).
Walking with Dinosaurs: Inside their WorldEditCamarasaurus, one of the more ancient macronarians, is a downloadable dinosaur in this app.
Appearances in other mediaEdit
Read more at the Prehistoric Park Wiki
An unidentified Titanosaur (presumed to be Borealosaurus, though this genus isn't considered a Titanosaur much) has appeared in the third episode, they became accidental additions to the park. However they have proven to be useful, such as in the fifth episode, one was used as a tow truck to get Nigel Marvin's jeep out of a Carboniferous swamp, as the jeep got trapped unexpectedly (Nigel was expecting a drier habitat when he was preparing to hunt giant bugs) and the jeep's engine got flooded by water and mud.