"Vogelgnathus", a New Mississippian Conodont Genus

Abstract

On the basis of bedding-plane apparatus material from Montana and discrete-element collections from the Illinois Basin in Indiana and Illinois , the new Chesterian (Upper Mississippian) genus Vogelgnathus is named, and V. campbelli (Rexroad) and a new species are described. Vogelgnathus has a seximembrate (Pa, Pb, M, Sa, Sb, Sc) apparatus plan that is similar to Ozarkodina, Pandorinellina, Gnathodus, Hindeodus, Lochriea, and Diplognathodus but with notable differences. Gnathodus is the probable ancestor. Pa elements of the type species are abundant at the topotype section near Vogel School, St. Clair County, Ill., but the small component elements are uncommon to rare. These factors made initial recognition of this multielement genus difficult.