Who did the Roman republic use for ambassadors? Senators? Equites?

Question:

Who did the Roman republic use for ambassadors? Senators? Equites?

A specific question would be as follows:
Before the second punic war (120 B.C.), the Romans sent a delegation to Saguntum in Spain to make a treaty. Would they have sent a Senator? A group of Senators? Equites?

Best Answer - Chosen by Asker: I tried looking for an answer but unfortunately nothing has been written who the ambassadors were. Only the names of the consuls.
http://www.mainlesson.com/display.php?au...
http://www.choice-one.net/punic_wars.htm...
http://www.romeartlover.it/storia3.html...