Idealized dinosaur biostratigraphy of the Judith River Formation.

Dates and stratigraphic nomenclature from Rogers et al. [10]. Faunal data from: 1, Sahni [12]; 2, Rogers and Brady [13]; 3, Marsh [3]; 4, Cope [14]; 5, Cope [15]; 6, Penkalski and Dodson [16]; 7, Ryan et al. [8]; 8, this study; 9, Leidy [17]; 10, Cope [18]; 11, Fiorillo and Currie [19]; 12, Fiorillo [20]; 13, Dodson [4]; 14, Freedman et al. [21]; 15, Schott et al. [22]; 16, Ryan [5]; 17, Ryan et al. [7]; 18, Longrich [6]. All taxa from terrestrial McClelland Ferry or Coal Ridge members. Asterisk (*) denotes holotype of key species. Abbreviations: D1-3, disconformities bounding depositional sequences of Woodhawk Member.