A Ph.D. in clinical psychology IS a doctorate in clinical psychology. There are two kinds of doctorates in clinical psychology - a Ph.D. or a Psy.D. A Ph.D is a DOctorate of Philosophy and a Psy.D. is a doctorate in psychology.
A PhD can do clinical work, and also is efficient in research. A Psy.D is geared more toward the clinical aspect of psychology, but not the research side.