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Numerous footprints of dinosaurs, pterosaurs and birds, together with arthropod tracks, have been discovered in the upper Cretaceous Uhangri Formation which crops out along the south-western coastline of South Korea. This ichnofauna contains the first pterosaur tracks reported from Asia. The digitigrade tridactyl manus impressions exhibit features of a typical pterosaur hand print. The pes impressions, however, show features that are different from pterosaur footprints reported previously: there is no visible trace of impressions of individual digits, and the toes are triangular or rounded in shape distally without distinct claw impressions. As these features clearly distinguish the Uhangri tracks from Pteraichnus and Purbeckopus, we assign them to a new genus, Haenamichnus which accommodates the new ichnospecies, Haenamichnus uhangriensis. The prints are five to six times larger than those of Pteraichnus, and are currently the largest pterosaur ichnites known. They show virtually no trace of the 5th phalange of the pes, indicating that they were made by pterodactyloids; moreover, features of the tracks suggest that they can be attributed to azhdarchids, the commonest pterosaur of the Late Cretaceous. The longest pterosaur trackway yet known from any track site (length 7.3 m) and consisting of 14 pairs of foot impressions, was also found in the Uhangri Formation and suggests that azhdarchids, at least, were competent terrestrial locomotors. The fossil track site at Uhangri represents the first occurrence of the tracks of pterosaurs, dinosaurs and web-footed birds all on the same level. This demonstrates that pterosaurs and birds visited the same habitat, but the large size disparity suggests that they occupied different ecological niches.

"Splitting" and "lumping" are perpetual problems in vertebrate, especially dinosaur, ichnotaxonomy. Chinese dinosaur ichnotaxonomy, which began in 1940, provides a series of interesting case studies, highlighting the dual problems of historical and dubious ichnotuonomy. Chinese Mesozoic tetrapod track types have been placed into 63 ichnospecies (one Triassic, 28 Jurassic, and 34 Cretaceous), exclusive of other, non-type ichnospecies or ichnota:J:a identified from China. Fifty-two (-83%) of these 63 tetrapod ichnospecies were placed in monospecific ichnogenerL At the ichnogenus level, we prune--either by recognizing nomina dubia or by synonymy-17 from the list of 53 dinosaurian ichnogenera (a 32% reduction), leaving 36 ichnotaxa that we consider valid. Most of the cuts affect Jurassic theropod ichnotaxa, which are reduced from 23 to only nine because most ichnogenera are subjective junior synonyms of Grallator and Eubrontes. Fewer Chinese Cretaceous ichnotaxa (only six of 21 ichnogenera) are obvious nomina dubill or subjective synonyms, suggesting greater east Asian endemism during this time. Because ichnospecies differences are subtle, we provisionally retain ichnospecies as valid pending detailed comparative analyses of congeneric ichnospecies. This synthesis is long overdue and is necessary to address problems of historical and provincial ichnotaxonomy, which severely hamper comparisons of tetrapod ichnofaunas in space and time.

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The skeletal record of tyrannosaurids is well-documented, whereas their footprint record is surprisingly sparse. There are only a few isolated footprints attributed to tyrannosaurids and, hitherto, no reported trackways. We report the world’s first trackways attributable to tyrannosaurids, and describe a new ichnotaxon attributable to tyrannosaurids. These trackways are from the Upper Cretaceous (Campanian - Maastrichtian) of northeastern British Columbia, Canada. One trackway consists of three tridactyl footprints, and two adjacent trackways consist of two footprints each. All three trackways show animals bearing southeast within an 8.5 meter-wide corridor. Similarities in depth and preservation of the tyrannosaurid tracks indicate that these three trackways were made by track-makers walking concurrently in the same direction. These trackways add significantly to previous osteology-based hypotheses of locomotion and behavior in Tyrannosauridae by providing ichnologic support for gregariousness in tyrannosaurids, and the first record of the walking gait of tyrannosaurids.

A diverse assemblage of dinosaur and bird tracks from Niobrara County, Wyoming, represents the first vertebrate ichnofauna reported from the bone-rich Lance Formation (Maastrichtian, Upper Cretaceous). The ichnofauna includes a hadrosaur track with skin impressions; three theropod track types, including the tetradactyl track Saurexallopus zerbsti (ichnosp. nov.); a tridactyl dinosaur footprint with a fusiform digit III; possible Tyrannosaurus tracks; four distinctive avian ichnites; and invertebrate traces. The footprints are generally well-preserved and so offer a unique insight into the ecology of a small river valley during the Maastrichtian.Saurexallopus zerbsti ichnosp. nov. from the Lance is similar to Saurexallopus lovei recently reported from the Maastrichtian, Harebell Formation, of northwestern Wyoming, but is represented by much better material, facilitating amendment of the ichnogenus. Skeletal equivalents for Saurexallopus are not currently known. Similarly, the tridactyl track with fusiform digit III is similar to footprints reported from the coeval Laramie Formation of Colorado and may also be similar to ichnogenus Ornithomimipus from the Edmonton Group of Alberta (though not necessarily of ornithomimid affinity). The hadrosaurian track with the skin impression is reminiscent of a similar ichnite reported from the Maastrichtian, St. Mary River Formation in Alberta, which is herein named Hadrosauropodus langstoni as part of a reassessment of Cretaceous ornithopod track ichnotaxonomy. Such correlations demonstrate the utility of tracks for local or regional biostratigraphy (palichnostratigraphy) in western North America. It is also clear that tracks add to our knowledge of the composition and distribution of dinosaurian and avian components of Maastrichtian faunas. In particular the bird tracks indicate a diversity of at least four species, one of which was a semi-palmate form, hith

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