Since the ichnogenus Selenichnus , subsequently renamed Selenichnites , was first introduced in 1987, nine ichnospecies have been assigned to the ichnotaxon. The records are from all of the continents and range in age from Cambrian to Jurassic. These occurrences are reviewed and are found to include a diversity of morphological forms, some of which we believe should not be included within Selenichnites as defined in the original diagnosis. Also some of these ichnotaxa are inadequately described and without named ichnotypes. Consequently we propose emended ichnogeneric diagnoses for Selenichnites and Limulicubichnus , an emended ichnospecies diagnosis for Selenichnites rossendalensis , and re-assignment of some of the published ichnospecies to two new ichnogenera, Crescentichnus and Faciemichnus . The ichnospecies here assigned to the two new ichnogenera are: C. antarcticus comb. nov., C. langridgei comb. nov., C. tesiltus comb. nov. and F. belosis comb. nov.. Herradurichnus , previously regarded as a junior synonym of Selenichnites , is retained and considered to be distinct from Crescentichnus .

Summary: Prints belonging to Pteraichnus are recorded and described from the Saltwick Formation (Middle Jurassic, Aalenian Stage) at Hayburn Wyke on the Cleveland Coast of Yorkshire, England. This is the first record of Pteraichnus from the region and from the British Isles, and is an important addition to its diverse vertebrate ichnofauna. It is also only the second record of pterosaur footprints from the British Isles and is the oldest known occurrence of Pteraichnus . Significantly, it suggests that the pterodactyloid pterosaurs evolved earlier than has previously been supposed.

Despite the Hebrides and Cleveland basins being geographically close, research has not previously been carried out to determine faunal similarities and assess the possibility of links between the dinosaur populations. The palaeogeography of both areas during the Middle Jurassic shows that there were no elevated landmasses being eroded to produce conglomeratic material in the basins at that time. The low-lying landscape and connected shorelines may have provided connectivity between the two dinosaur populations. The dinosaur fauna of the Hebrides and Cleveland basins has been assessed based primarily on the abundant ichnites found in both areas as well as their skeletal remains. In the two basins, the dinosaur faunas are very similar, consisting of non-neosauropod eusauropods, a possible basal titanosauriform, large and small theropods and ornithopods and europodan thyreophorans. The main difference in the faunas is in the sizes. In the Cleveland Basin, the ichnites suggest that there were medium and large theropods alongside small to medium sized ornithopods, whereas, in the Hebrides Basin, the theropods were from small to large and the ornithopods were medium to large. It is suggested that migrations could have taken place between the two areas during the Middle Jurassic. A tentative food chain from the herbivorous dinosaurs to the top predators can be inferred from the footprints.

The invertebrate trace fossils Selenichnites rossendalensis and Crescentichnus tesiltus are recorded and described from the Middle Jurassic Gristhorpe Member of the Cloughton Formation of the Cleveland Basin. This is the first record of these ichnospecies from the basin and now completes the occurrence of these and other traces assumed to have been made by limulids from all three non-marine formations of the Ravenscar Group.