Revision and redescription of some Lower Mississippian trilobites from the Chouteau Formation (Kinderhookian) of central Missouri

Abstract

Recent recovery of specimens of new and previously poorly known Lower Mississippian trilobite species from the Chouteau Formation of central Missouri has prompted their comparison with contemporaries of Eurasia. Two new genera,DixiphopygeandComptonaspis, are proposed utilizingBrachymetopus armatusVogdes andProetus swallowiShumard, respectively, as type species. Two species are assigned toBrachymetopusandNamuropyge, genera previously unknown from Chouteau strata. The first complete dorsal exoskeletons of the genusProetidesWinchell are described and illustrated. Indeterminate species ofBreviphillipsiaandPiltoniaare described and illustrated.