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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]

Hybodontoid and nonhybodontoid sharks are described from the Lower Triassic Vega-Phroso Siltstone Member of Sulphur Mountain Formation on the basis of newly discovered material. The age of the classic fossil site ‘Wapiti Lake’ in the Canadian Rocky Mountains is discussed on the basis of new field data and one conodont found in association. Preliminary results suggest that these elasmobranch remains are between early Smithian and Spathian in age. Apart from the enigmatic genus Listracanthus and previously reported edestoids, the shark fauna consists of at least one hybodont, at least two questionable hybodontoid genera and an elasmobranch of enigmatic affinities, represented by peculiar denticles only and described as ‘genus A’ incertae sedis. The presence of the only previously reported hybodont genus, cf. Palaeobates, is erroneous. The largest specimen represents the most complete Early Mesozoic shark known. The heterodonty of its dentition, fin spine morphology and the short, robust body shape imply it represents a member of a new family of shark, Wapitiodidae fam. nov., and is described here as Wapitiodus aplopagus gen. et sp. nov. The unique dental morphology shows affinities to Polyacrodus but clearly differs in the complete lack of side cusps. Wapitiodus gen. nov. possesses a primitive fin spine structure. The tooth crowns are entirely blunt in the distal (posterior) tooth files, and are acuminate-unicuspid in several anterior files. Tooth morphology, the shape of the basal cartilages, the proximal insertion of the fin spines and the pectoral fin structure are interpreted as diagnostic characters for this new genus, and possibly for the Wapitiodidae fam. nov. The majority of observed characters appear to be primitive and are reminiscent of Palaeozoic sharks, however, and these features include dorsal fin spine morphology and gross skull anatomy. A second species, provisionally placed in the same genus, is described as Wapitiodus homalorhizo sp. nov. Wapitiodus homalorhizo sp. nov. can be distinguished from W. aplopagus gen. et sp. nov. by the proportions of the fin spines, tooth morphology and possibly the body shape. Several isolated teeth and other fragmentary material are referred to either Wapitiodus gen. nov. sp. indet. or to ? Polyacrodus sp. (Polyacrodontidae gen. et sp. indet.). A third genus of elasmobranch ( incertae sedis) is described as ‘Genus A’ and is recognized by its peculiar scales. © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society, 2007, 149, 309–337. [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]