Middle Campanian ammonites and inoceramids from the Wolfe City Sand in northeastern Texas
The middle Campanian Wolfe City Sand in northeastern Texas yields a distinctive ammonite and inoceramid fauna with Patagiosites sp., Placenticeras sp., Hoplitoplacenticeras ( Hoplitoplacenticeras ) minor n. sp., Baculites mclearni Landes, 1940, Trachyscaphites spiniger (Schlüter, 1872) porchi (Adkins, 1929), Inoceramus ( Cordiceramus ) azerbaidjanensis Aliev, 1939, and I. ( Endocostea ) balticus Boehm, 1907. The last-named four species allow a direct correlation with the Baculites mclearni zone of the Western Interior of the United States. The base of this zone has been dated at 79.9 ± 3.2/79.2 ± 1.6 Ma on the basis of K/Ar determinations on biotite from a bentonite. Inoceramus azerbaidjanensis is also known from the Campanian of the U.S.S.R. in Azerbaidjan (where the species was first described), western Turkemenia, Georgia, the northern Caucasus, the Crimea, and Donbass.