The Mazarn Shale is an Early Ordovician geologic formation in the Ouachita Mountains of Arkansas and Oklahoma. This interval was first described in 1892, but remained unnamed until 1918 as part of a study by U.S. Geological Survey geologist Hugh Dinsmore Miser.

Paleofauna Graptolites

Caryocaris C. wrighti Cryptograptus C. antennarius Didymograptus D. caduceus D. caduceus nana D. extensus D. filiformis D. nitidus D. similis Diplograptus Glossograptus G. hystrix Mesograptus Phyllograptus P. typus Retiograptus Tetragraptus T. clarkei T. fruticosus T. quadribrachiatus T. pendens T. serra T. similis

See also

List of fossiliferous stratigraphic units in Arkansas Paleontology in Arkansas

References