Rear panel of the Pala d'Oro, Venice
Oil on panel?
St. Mark's Cathedral, Venice
The apostles can be identified by inscriptions on the dark band at their feet:
Left to right along the upper row: Matthias or Paul (inscription is illegible), Andrew (holding a cross in his left hand), John, Peter (keys), James the Greater (pilgrim's staff), Bartholomew (inscription lost, but note flaying knife).
Left to right along the lower row: Philip, Jude Thaddeus, Thomas, Matthew, Simon, and another apostle whose label is lost.
The apostle on the far right is almost certainly James the Less. In Latin he is called Jacobus Minor, and the word minor sometimes leads artists to make him beardless so he will look younger than the other James. Compare the same tactic in the predella of a polyptych in Croatia.
This image in full resolution
More of the apostles as a group
Photographed at St. Mark's by Richard Stracke, shared under Attribution-NonCommercial-ShareAlike license.