TRILOBITES FROM LOWER MISSISSIPPIAN STARVED BASIN FACIES OF THE SOUTHERN UNITED-STATES

A distinctive trilobite fauna occurs within condensed statigraphic sec tions of the Lower Mississippian (Tournaisian) Chappel Limestone of th e Llano region of Texas, the Welden Limestone of Oklahoma, and the Cho uteau Limestone of Union County, Illinois. The seven species comprisin g this fauna are interpreted to have inhabited sediment-starved basina l environments. The starved-basin facies existed in the south-central United States throughout the Tournaisian (Kinderhookian to Osagean). T wo species from this fauna, Australosutura llanoensis, and Carbonocory phe planucauda, are new. The remaining five species, Griffithidella do ris (Hall), Griffithidella alternata (Girty), Carbonocoryphe depressa (Girty), Thigiffides roundyi (Girty), and Pudoproetus chappelensis (He ssler), are restricted to starved-basin facies.