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Fossil material from the Maastrichtian part of the Scollard Formation is identified as belonging to an acanthomorph fish. An articulated specimen, preserved in part and counterpart, is a member of the paracanthopterygian order Percopsiformes, based on it having a full neural spine on the second preural centrum and two epurals in the caudal skeleton (both paracanthopterygian characters), as well as six branchiostegal rays and an anterodorsal excavated margin on the opercle (percopsiform characters). We name this as a new genus and species, Lindoeichthys albertensis. A phylogenetic analysis with no prior constraints recovered a single most-parsimonious tree with the new taxon placed as the sister group to a clade containing the Palaeocene Montana genus Mcconichthys + Percopsidae. However, this analysis did not recover the traditional percopsiforms (including Aphredoderidae and Amblyopsidae) as monophyletic. A second analysis, in which we constrained the traditional members of the Percopsiformes to be monophyletic, resulted in the new species being placed as the sister group to Percopsis. The articulated percopsiform specimen from the Pisces Point locality allows isolated dentaries from vertebrate microfossil localities to be identified as being from a member of that group. These isolated elements first appear in the late Campanian Judith River Group of Alberta and the Kaiparowits Formation of Utah, documenting that percopsiform fishes were present in the Western Interior of North America at least 75 Ma ago. [ABSTRACT FROM AUTHOR]

A single block containing five articulated osteoglossomorphs was recovered from the Paskapoo Formation of southern Alberta, during development of a residential community in Calgary. Two of the specimens represent a new species of † Joffrichthys , and the other three represent a new genus and species of osteoglossomorph. The discovery of a new species of † Joffrichthys led us to re-examine the type species and to recode many of the characters that have been used in phylogenetic analyses. In particular, we interpret the caudal skeleton of † Joffrichthys to have 16 branched principal rays, not 15, which indicates this genus does not belong in Osteoglossiformes, and removes it from the osteoglossid/heterotidine affiliations previously reported. We assessed the relationships of the two new taxa using a modified data matrix including new outgroups and corrected data, with and without the inclusion of † Ostariostoma. Our results show that † Joffrichthys is a basal member of the superorder, and not a member of the Heterotidinae, but the other new taxon is left incertae sedis in the superorder. We also provide data on the early history of osteoglossomorphs in North America provided by isolated elements from Cretaceous and Palaeocene microfossil sites that complement and supplement that provided by articulated specimens. [ABSTRACT FROM AUTHOR]

The Sulphur Mountain Formation in Alberta, Canada, comprises shales, siltstones, and limestones laid down on the continental shelf and shoreline along the western margin of the North American Craton during the Early and Middle Triassic. At least 13 taxa of fossil marine fishes have been found at a number of Triassic localities along the Front Ranges and foothills in Alberta. Common taxa (Boreosomus, Birgeria, Bobasatrania, Australosomus, Saurichthys, parasemionotids, and coelacanths) found at localities in Alberta are similar to those found at the classic Lower and Middle Triassic localities near Wapiti Lake, British Columbia, and in East Greenland, Spitzbergen, Madagascar, and China. The occurrence of Lower Triassic fishes in western Alberta shows that this fauna was widespread, occurring over at least 1000 km of shoreline, and that ecological and environmental factors were similar along the western edge of the Panthalassic Ocean during the Early Triassic. [ABSTRACT FROM AUTHOR]

Horseshoeichthys armaserratus, gen. et sp. nov., (Clupeomorpha: Ellimmichthyiformes: Sorbinichthyidae) is described from the Horseshoe Canyon Formation (Maastrichtian), Albertosaurus bonebed locality, Alberta, Canada. Horseshoeichthys armaserratus is classified as an ellimmichthyiform based on the following characters: the presence of a sixth infraorbital with a sensory canal that leads to the fifth infraorbital, absence of a supraorbital bone, subrectangular predorsal scutes, parietals in contact with each other at the midline, and two supramaxillae. The specimen is classified in the Sorbinichthyidae Family as it has abdominal ribs articulating in pits on the centra, posterior spines on predorsal scutes, and absence of a median spine on predorsal scutes. A new genus and species is proposed based on the presence of (anteriorly) Y-shaped mesethmoid, supraorbital, subrectangular predorsal scutes with coarse, rounded serrae on the posterior margin and a large anterior projection, scales with serrae on the circuli, and two postcleithra. This specimen represents the first freshwater ellimmichthyiform from the Upper Cretaceous of North America and the highest paleolatitude (59°N) occurrence known for the family. Furthermore, the dentary and centra have distinctive morphologies that are matched by specimens in microvertebrate localities from three underlying formations, including the Milk River Formation (Santonian), which indicates at least a 14 million year history for this lineage. Horseshoeichthys armaserratus, gen. et sp. nov., (Clupeomorpha: Ellimmichthyiformes: Sorbinichthyidae), de la localité du gisement d'ossements d'Albertosaurus de la Formation de Horseshoe Canyon (Maastrichtien), en Alberta, au Canada, est décrit. Horseshoeichthys armaserratus est affecté aux ellimmichthyiformes à la lumière des caractères suivants : la présence d'un sixième sous-orbitaire présentant un canal sensoriel qui mène au cinquième sous-orbitaire, l'absence d'un os sus-orbitaire, des plaques osseuses pré-dorsales sub-rectangulaires, des pariétaux en contact les uns avec les autres au niveau de la ligne médiane et deux sus-maxillaires. Le spécimen est affecté aux sorbinichthyidés puisqu'il présente des côtes abdominales s'articulant dans des fosses sur le centrum et des épines postérieures sur les plaques osseuses pré-dorsales, et que ces dernières n'ont pas d'épine médiane. Un nouveau genre et une nouvelle espèce sont proposés à la lumière de la présence d'un mésethmoïde (antérieurement) en forme de Y, d'un sus-orbitaire, de plaques osseuses pré-dorsales sub-rectangulaires présentant des stries arrondies et épaisses sur leur bord libre postérieur et une grande projection antérieure, d'écailles avec des stries sur le circulus et de deux postcleithra. Ce spécimen représente le premier ellimmichthyiforme d'eau douce du Crétacé supérieur de l'Amérique du Nord et l'exemple connu de cette famille provenant de la plus haute paléolatitude (59oN). En outre, le dentaire et le centrum présentent des morphologies particulières semblables à celles de spécimens trouvés dans des localités de microvertébrés de trois formations sous-jacentes, dont la Formation de Milk River (Santonien), ce qui indique une histoire d'au moins 14 millions d'années pour cette lignée. [ABSTRACT FROM AUTHOR]

We here report the first documented occurrence of a gonorynchiform from the Mesozoic of Canada, represented by disarticulated material recovered from multiple localities in the Lethbridge Coal Zone, in the Late Cretaceous Campanian upper Dinosaur Park Formation of southern Alberta. Despite the preservation of these specimens as disarticulated and isolated microvertebrate material, we can identify this fish as the gonorynchid Notogoneus. Although this material was recovered from estuarine settings, the local environment was freshwater, and this occurrence does not constitute evidence that this species of Notogoneus was amphidromous, as has previously been hypothesized for early gonorynchids. We offer suggestions regarding the whole-body anatomy of the fish represented in our sample through comparisons with articulated specimens of Notogoneus osculus from the Green River Formation as well as with modern comparative material. Such details include a narrow mouth in a ventral position and probable possession of branchial tooth plates, from which aspects of the ecology of this fish can be deduced, such as durophagy and a probable demersal environmental preference. Additionally, these comparisons highlight the mosaic evolution of early gonorynchids, combining a primitively chanid-like vertebral anatomy and a more derived, Gonorynchus-like jaw. [ABSTRACT FROM AUTHOR]

The replacement names Homalodontus nom. nov. ( Homalodontidae nom. nov.) are proposed for the Early Triassic shark Wapitiodus Mutter et al., 2007 (Wapitiodidae Mutter et al., 2007), preoccupied by the Triassic conodont Wapitiodus Orchard, 2005 (Gondolellidea Lindström, 1970 ). © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society, 2008, 154, 419–420. [ABSTRACT FROM AUTHOR]