Biofacies interpretation of Star Peak and partly equivalent basinal conodonts is based upon sedimentologically and paleontologically determined lithofacies relationships as well as a regional paleogeographic model.

Late Spathian transgression initiated Star Peak sedimentation. Deep shelf conditions represented by the lower member of the Prida Formation supported an abundant neospathodid fauna (Neospathodus homeri and N. triangularis) succeeded by a neogondolellid fauna (Neogondolella jubata and N. timorensis). At the same time, restricted shallow marine waters to the east were sparsely populated by neogondolellids (Tobin and Dixie Valley Formations). During the Anisian, deep shelf conditions characterized all of Star...