Cretaceous invertebrate and selachian fossil assemblage from the Juana Lopez Member of the Mancos Shale near Herrera, west-central New Mexico
— Spencer G. Lucas and Sally C. Johnson

An invertebrate fossil assemblage from the Juana Lopez Member of the Mancos Shale near Herrera in the Rio Puerco Valley of Sandoval County, New Mexico, includes the index bivalves Lopha lugubris (Conrad) and Inoceramus dimidius White and the index ammonites Prionocyclus macombi Meek, Prionocyclus novimexicanus (Marcou) and Scaphites whitfieldi Cobban. There is a meager selachian assemblage composed of Ptychodus whipplei Marcou, Ptychodus anonymus Williston Scapanorhynchus raphiodon (Agassiz), Cretolamna sp. and Squalicorax sp., of which only P. whipplei is common. P. whipplei is a characteristic Turonian species of Ptychodus and is common in the Juana Lopez Member.