New information on two Late Cretaceous (Turonian) fishes from Lac des Bois, Northwest Territories, Canada

Abstract

Abstract:Fishes from Turonian deposits at Lac des Bois, Northwest Territories, Canada, have previously been described based on material from calcareous mudstone concretions collected in 1969. A more recent collecting trip to the locality in 2010 led to the discovery of additional fossil fishes in a shale layer. These fishes, preserved in a different manner from the earlier collections, provide new information and allow reinterpretations of two previously described fishes, Aquilopiscis wilsoni (Pachyrhizodontidae) and Avitosmerus canadensis (Euteleostei). Although the new material allows a better understanding of these two fishes, it does not change our ideas about their relationships. Avitosmerus canadensis remains in the Euteleostei with relationships uncertain, and Aquilopiscis wilsoni is confirmed as a member of the Pachyrhizodontidae.

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

“…16 ), as well as decreases the gradient of the north-south or central-south community boundary positioned between WIS localities in present-day South Dakota and Kansas during early and mid-Turonian times ( Kilmury & Brink, 2022 ). Since there was only a minor increase in specimens belonging to taxa shared between the MB Keld Member and coeval Northwest Territories Unit E vertebrate assemblages, which include Cimolichthys sp., Enchodus petrosus , and Ichthyodectes ctenodon , nor recognition of taxa specific to the Unit E assemblage ( Cumbaa & Murray, 2008 ; Murray & Cumbaa, 2013 , 2015 ; Murray, 2016 ; Cumbaa et al, 2018 ) from the lower and middle Favel Formation (Keld Member) horizons analyzed in this study, a central subprovince distinct from northern one is further supported for late Cenomanian to early Turonian time ( Kilmury & Brink, 2022 ).…”