Microvertebrate faunal assemblages of the Favel Formation (late Cenomanian-middle Turonian) of Manitoba, Canada

Abstract

Microvertebrate assemblages of the Upper Cretaceous (late Cenomanian to mid-Turonian) Favel Formation of Manitoba are formally described for the first time. New vertebrate occurrences from the Favel Formation include the actinopterygians Caturidae indet., cf. Albulidae incertae sedis, Micropycnodon kansasensis, Pachyrhizodus minimus, Protosphyraena sp., Thryptodus loomisi, chondrichthyans Ischyrhiza cf. mira, I. texana, Ptychodus marginalis, P. occidentalis, and P. rhombodus, the avian cf. Ichthyornis sp., the reptile Testudines indet., and an unknown taxon referred to as Vertebrate A. Changes in faunal occurrences throughout the formation suggest an offshore open marine environment for the lower and middle horizons and nearshore marine for the upper horizon, represent ing mid- and late stages of the Greenhorn third-order marine cycle. This newly described diversity increases biogeographic affinities of the late Cenomanian to mid-Turonian vertebrate assemblages of Manitoba with central WIS localities in South Dakota and Kansas, providing additional support for a central vertebrate biogeographic subprovince during late Cenomanian to early Turonian times, as well as WIS localities further south in Texas decreasing the gradient of the north-south or central-south community boundary during early and mid-Turonian times.