Early Turonian acanthomorphs from Lac des Bois, Northwest Territories, Canada

ABSTRACT

Recent collecting in fossiliferous deposits at Lac des Bois, Northwest Territories, Canada, has produced the first record of acanthomorph fishes from the locality. Two specimens of acanthomorph, each representing a different taxon, were among the fishes collected. One of these is complete and well preserved; we here describe and name this fish, Boreiohydrias dayi, gen. et sp. nov. This fish is a polymixiiform, but it cannot be placed in any previously named family and we here give it a new family, Boreiohydriidae. The second acanthomorph is fragmentary; we describe it but do not formally name it. The relationships of early acanthomorph fishes are not easily determined, and still need much study, as do their living relatives. These two Turonian fishes are early members of the Acanthomorpha, which is first represented in the early Cenomanian in the Western Interior Seaway.

ACKNOWLEDGMENTS

We are grateful to R. Day (CMN) and R. Holmes (CMN and UALVP) for collecting material from Lac des Bois, and companionship in the field. We also thank the people of Norman Wells for their hospitality and generosity, particularly L. Wallace, C. Salikin, and S. and J. Kivi. Our thanks to S. Stewart (University of Alberta) for checking our Greek. We thank the reviewers and associate editor for their very helpful comments; in particular, we are grateful to J. Moore for correcting our identification and providing detailed comments and references for polymixiiforms. The material described here was collected during field work funded by the Polar Continental Shelf Program (S.L.C.), the Canadian Museum of Nature (S.L.C.), and National Science and Engineering Research Council of Canada Discovery Grant 327448 (A.M.M.). Field work was conducted under Aurora Research Institute Scientific Research Licence No. 14714 issued to S. L. Cumbaa.

Handling editor: Matt Friedman