Abstract

The distinctive cheilostome bryozoan Stictostega durhami Shaw, 1967, from the Upper Campanian Ozan Formation of Arkansas, is redescribed and its relationships are reconsidered. Originally interpreted as a hippothoid ascophoran, the presence of a cryptocystal frontal shield and other characters suggest that it is a coilostegan anascan. Pores in the frontal shield are inferred to have served for the passage of parietal muscles (or their ligaments), which operated on the frontal membrane to raise hydrostatic pressure and protrude the lophophore in the same way as recently demonstrated in living Macropora. Stictostega is provisionally interpreted as a stem-group macroporid.

You do not currently have access to this article.