How did the apostles and other disciples distinguish between themselves during the time of Jesus' public ministry?

We read in Mtt 26:14 : > Then one of the twelve, called Judas Iscariot, went unto the chief priests... On a number of occassions including the Last Supper, 'the twelve' are referred to as 'disciples'. Other than the twelve whom we know as Apostles, Jesus also had 72 disciples . After the Lord's ascension, the hierarchy would become prominent with the Apostles having exclusive meetings and decision making . But, how did the apostles and other disciples distinguish between themselves during the time of Jesus' public ministry ? For instance, were they addressed as Apostle Peter, Disciple Mark etc ? Are there any apocryphal writings available on the subject ?