for evidentiary hearing do I the custodian parent have to be there if I have an atone to represent me?

Well . . . probably.  The "telephonic appearance" and other rules are not designed for evidentiary hearings.  If you are a witness -- and I presume this is a custody case involving you and your child, so I presume you are -- there is no substitute to you being available, in court, for examination and cross-examination (sometimes, video appearances are permitted if necessary).  It is hard to see how you would NOT be a witness, but you did not say much about what kind of hearing it is, or why it is being held, so it is difficult to be sure.  if you have questions of this sort, your first call should be to your lawyer to ask who is to be called; if you cannot be present, make sure that your absence has been cleared with the court in advance.