for a nearly complete skeleton and skull from the deposits, an unnamed but new form of snapping turtle is known, Adocus and Basilemys represent the diversity of primitive trionychoids, and the softshelled turtles Apalone, Aspideretoides, and a new form, are also present. Fragmentary material from the choristodere Cteniogenys, and many well-preserved skulls and skeletons of its relative Champsosaurus, is present among the fauna of the Dinosaur Park Formation, representing an extinct group of semi-aquatic animals with crocodilian features that spanned the globe for much of the Mesozoic and Cenozoic. Mosasaurs and plesiosaurs are both known from the Dinosaur Park Formation, though mosasaurs are only represented by the teeth of Plioplatecarpus from the upper deposits, and apart from the relatively complete elasmosaurid Fluvionectes, plesiosaurs are only known from isolated and incomplete elements. Two or three true crocodilians are known, including the named genera Leidyosuchus and Albertochampsa. A rich and diverse vertebrate assemblage is known from the Dinosaur Park Formation, with the lower region, excluding the Lethbridge Coal Zone, being formed by terrestrial and coastal deposits. Microfossil sites are common, but a taphonomic bias is present in the formation towards the better preservation of large-bodied animals like Panoplosaurus, which is 63% complete. Six small lizards are known, representing five different families, with the teiids Socognathus and Glyptogenys, the xenosaurid Exostinus, the helodermatid Labrodioctes, the necrosaurid Parasaniwa, and the varanid Palaeosaniwa. No snakes are known, which, while it contrasts with the modern diversity of the group, does correspond with the rarity of the group during the Cretaceous. Two pterosaurs have been found, the azhdarchid Cryodrakon and an unnamed pterodactyloid. All three major types of mammal present in the Cretaceous have been found in the Dinosaur Park Formation, Multituberculata, Marsupialia and Placentalia. The named multituberculates include Cimexomys, Cimolodon, Cimolomys, Meniscoessus, and Mesodma. Marsupials are represented by the taxa Alphadon, Eodelphis, Pediomys, and Turgidodon, and placentals by Cimolestes, Gypsonictops, and Paranyctoides, though all the material represents isolated partial skull or skeletal bones, or isolated teeth. While no other dinosaurs were recovered at the same sites as any Panoplosaurus specimens, correlation and comparisons of localities throughout the Dinosaur Park Formation show it coexisted with a large variety of animals. The herbivorous fauna of the Dinosaur Park Formation can be divided into two Megafaunal Assemblage Zones, defined as the lowest directly above the Oldman Formation, and the deposits above those, where the common ceratopsid Centrosaurus and hadrosaurid