Among the men named James (יעקב "Holder of the heel; supplanter"; Standard HebrewYaʿaqov, Tiberian HebrewYaʿăqōḇ), in the New testament, whose number may be increased by the variety of epithets and euphemisms applied to them, James son of Alphaeus (or Clopas), is called the Less or the Younger to distinguish him from Saint James the Great and Saint James the Just. He was a brother of the apostle Matthew and the son of Mary (whom Roman Catholics insist must not be confused with Mary, the mother of Jesus).
He appears in the slightly varying lists of the Twelve Apostles, as does James the Great: Matthew 10:3; Mark 3:18; Luke 6:15; Acts 1:13. He is also mentioned when his mother appears in Mark 15:40 (where he is labelled "less", "little" or "younger" depending on the translation) and Matthew 27:56; her marriage to Clopas is probably mentioned in John 19:25.
Not much is known about his later ministry. Eusebius of Caesarea reported a tradition identifing him with James the Just, the head of the early Christian Church in Jerusalem, but modern biblical scholars usually distinguish them.
External link
Catholic Encyclopedia: (http://www.newadvent.org/cathen/08280a.htm) Saint James the Less
StJames is the brother of John, the sons of Zebedee.
The possibility that a cult of James was instituted to supplant the Galician cult of Priscillian (executed in 385) who was widely venerated across the north of Spain as a martyr to the bishops rather than as a heretic should not be overlooked.
StJames suffered martyrdom A.D. 44 (Acts 12:2), and, according to the tradition of the early Church, he had not yet left Jerusalem at this time (see Clement of Alexandria, Stromateis, VI; Apollonius, quoted by Eusebius, Hist.
James, to distinguish him from the other apostle of the same name, the son of Zebedee, was called the Less; which appellation is supposed to have taken its rise, either from his having been called later to the apostleship than the former, or from the lowness of his stature, or from his youth.
James governed that church in perpetual dangers, from the fury of the people and their violent persecutions; but his singular virtue procured him the veneration of the Jews themselves.
The episcopal throne of St. James was shown with respect at Jerusalem, in the fourth century.