They both belong to the family Diplodocidae, but they're still different species. The Brontosaurus is thinner, and has different shoulder blades.

For a long time, people thought they were just adult and children of the same species, so they used the the name Brontosaurus for both of them, but found out that they were different species in the end.

I-I knew that. But it's still the 18th century now, and they still haven't discovered that, so I can still call them Bronto!

What's up with that!?

Their name means thunder...? They have the same name as you, Ikazuchi.

Ikazuchi!?

The Pteranodon is Mikazuki.

Uh huh, it's the name Nagato gave them. This one is Ikazuchi!

The Ankylosaurus is Yamakaze.

The Deinonychus is Murakumo.

The Spinosaurus is Nenohi.

Since all of them are strong, and cute!

There are still others Nagato hasn't named yet. Nagato only started calling them like this since a year ago.

Shimakaze only crossed over to this time 3 months ago, so it's probably a strange way of saying it.

The Triceratops is Ooshio.