COSMOPOLITAN CONODONTS IN THE SHURTLEFF CONCRETION HORIZON, UPPER CASHAQUA SHALE, SONYEA GROUP, MIDDLE FRASNIAN (UPPER DEVONIAN), APPALACHIAN BASIN IN WESTERN NEW YORK STATE

The Shurtleff Concretion Horizon in the upper Cashaqua Shale, Sonyea Group, can be traced from the Lake Erie shore eastward to Naples, NY near Canandaigua Lake. The concretions, typically just below the base of the Rhinestreet black shale, contain a distinctive barite replaced goniatite fauna of Manticoceras sinuosum sinuosum Hall, 1843 and Tornoceras uniangulare obesum Clarke, 1897, as well as Acanthoclymenia neapolitana Clarke 1892, Prochorites alveolatus (Glenister, 1958), and Aulatornoceras eifliense (Steininger 1849). Conodonts from the Shurtleff horizon include Ancyrognathus ancyrognathoideus (Ziegler, 1958), Ancyrodella nodosa Ulrich and Bassler, 1926, Icriodus symmetricus Branson and Mehl, 1934, Palmatolepis bohemica Klapper and Foster, 1993, P. gatovskyi Bardashev and Bardasheva, 2012, P. punctata (Hinde, 1879), P. reimersi Bardashev and Bardasheva, 2012, and P. spinata Ovnatanova and Kuz’min, 1991 which indicate FZ 6 of the thirteen-part Frasnian conodont zonation. In New York State FZ 5 starts at or near the base of the Cashaqua Formation, defined by the first occurrence of P. punctata; the base of FZ 7, defined by the first occurrence of Ozarkodina nonaginta Klapper, Kuzmin and Ovnatanova, 1996, is in the lower Rhinestreet Formation. A fauna very similar to that in the Shurtleff Horizon has been described from Tajikistan, central Asia, and assigned to the upper transitans Zone, which is equivalent to FZ 4, and lower punctata Zone, equivalent to FZ 5, based on a different interpretation of Palmatolepis puncata, where older forms are assigned to a different species and a younger morphotype is considered the zonal indicator. Cosmopolitan conodonts in the Upper Devonian allow refined correlation, but taxonomic interpretation must be consistent.