Cenomanian to Turonian
Texas to Montana
Original presentation: Ammonites swallovi
Original publication: Shumard. 1860 [p. 591].
Types: “The whereabouts of Shumard’s type material is not known; presumably it is lost” (Stephenson, 1953, p. 209). “White (1883, p. 39, pl. 18, fig. 1) reproduced a photograph of a drawing of Ammonites swallovii; this drawing was made by A. R. Roessler under Shumard’s direction, and may be accepted as an illustration of one of the original types” (Stephenson, 1953, p. 208).
Type locality: “four and a half miles north of Sherman, and bluffs of Red River in Fannin and Lamar Counties” (Shumard, 1860 quoted in Stephensen, 1953, p. 209).
Type horizon: “the exact age of the species is unknown” (Kennedy and Cobban, 1990a, p. 138).
PaleoDB taxon number: 145851.
References: Stephensen (1953); Kennedy and Cobban (1990a).