comma with apposition: the T. rex, the biggest known

[lady_of_the_rings]

In the following sentence I use the relative wich yo explain a characteristic of the animal, but if I want to say a characteristic of the second is correct to use a comma after the subject?

This dinosaur belongs to a group called the hadrosaurs, which are faster than the Tyrannosaurus rex, the biggest known carnivorous dinosaur.

thanks!

 

[Lexiphile]

The comma is correct.
This is another example of the question of the "essential" nature of the dependent clause. In your sentence, everything you wrote in blood-red can be left off and the sentence still makes perfect sense. So the clause is non-essential. Therefore it should have a comma before it.

That is the most reliable test: does the sentence sound complete and correct if the dependent clause is omitted? If so, use a comma.

 

[lady_of_the_rings]

Thanks Lexiphile!! =)