Reinterpretation of Stictostega Shaw, 1967, an Upper Cretaceous cheilostome bryozoan from Arkansas

The distinctive cheilostome bryozoan Stictostega durhami Shaw, 1967, from t he Upper Campanian Ozan Formation of Arkansas, is redescribed and its relat ionships are reconsidered. Originally interpreted as a hippothoid ascophora n, the presence of a cryptocystal frontal shield and other characters sugge st that it is a coilostegan anascan. Pores in the frontal shield are inferr ed to have served for the passage of parietal muscles (or their ligaments), which operated on the frontal membrane to raise hydrostatic pressure and p rotrude the lophophore in the same way as recently demonstrated in living M acropora. Stictostega is provisionally interpreted as a stem-group macropor id.