Phylogenetic analysis of Bell and Chiappe (2015) showing the derived placement of Fumicollis hoffmani within the Hesperornithiformes (grey box).

Time calibration is based on reported ages of known fossils. Body silhouettes are shown to represent approximate size differences among hesperornithiforms, scaled to a 6 foot human (lower right) based on geometric scaling of the tarsometatarsi and femora of known specimens. Node A is united by five unambiguous synapomorphies (see [8] for details). Abbreviations: ALB, Albian; CEN, Cenomanian; CMP, Campanian; CON, Coniacian; MAA, Maastrichtian; SNT, Santonian; TUR, Turonian.