The holotype of Deinocheirus mirificus was collected by the 1965 Polish-Mongolian Palaeontological Expedition at Altan Uul III in the southern Gobi of Mongolia. Because the holotype consists mostly of giant forelimbs (2.4 m in length) with scapulocoracoids, for almost 50 years Deinocheirus has remained one of the most mysterious dinosaurs. The mosaic of ornithomimosaur and non-ornithomimosaur characters in the holotype has made it difficult to resolve the phylogenetic status of Deinocheirus. Here we describe two new specimens of Deinocheirus that were discovered in the Nemegt Formation of Altan Uul IV in 2006 and Bugiin Tsav in 2009. The Bugiin Tsav specimen (MPC-D 100/127) includes a left forelimb clearly identifiable as Deinocheirus and is 6% longer than the holotype. The Altan Uul IV specimen (MPC-D 100/128) is approximately 74% the size of MPC-D 100/127. Cladistic analysis indicates that Deinocheirus is the largest member of the Ornithomimosauria; however, it has many unique skeletal features unknown in other ornithomimosaurs, indicating that Deinocheirus was a heavily built, non-cursorial animal with an elongate snout, a deep jaw, tall neural spines, a pygostyle, a U-shaped furcula, an expanded pelvis for strong muscle attachments, a relatively short hind limb and broad-tipped pedal unguals. Ecomorphological features in the skull, more than a thousand gastroliths, and stomach contents (fish remains) suggest that Deinocheirus was a megaomnivore that lived in mesic environments.

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Four heteropod lizard trackways discovered in the Hasandong Formation (Aptian-early Albian), South Korea assigned to Sauripes hadongensis, n. ichnogen., n. ichnosp., which represents the oldest lizard tracks in the world. Most tracks are pes tracks (N = 25) that are very small, average 22.29 mm long and 12.46 mm wide. The pes tracks show “typical” lizard morphology as having curved digit imprints that progressively increase in length from digits I to IV, a smaller digit V that is separated from the other digits by a large interdigital angle. The manus track is 19.18 mm long and 19.23 mm wide, and shows a different morphology from the pes. The predominant pes tracks, the long stride length of pes, narrow trackway width, digitigrade manus and pes prints, and anteriorly oriented long axis of the fourth pedal digit indicate that these trackways were made by lizards running bipedally, suggesting that bipedality was possible early in lizard evolution.

a b s t r a c tIn 1990, five well-preserved pterosaur trackways were discovered in the Kitadani Formation (Lower Cretaceous) of the Kitadani Dinosaur Quarry, Fukui Prefecture, Japan. They occur on the surface of an isolated dark grey siltstone slab (70 Â 50 cm) along with amphibian and bird tracks as well as feeding marks. All pterosaur trackways (a total of 64 imprints) show a clear quadrupedal gait pattern comprising manus and pes prints which reflect their detailed anatomy of the feet. Manus and pes imprint is very small, average 22.6 mm and 21.9 mm long, respectively. The manus has an anteriorly oriented digit I imprint with a medially oriented hook-like sharp claw mark, which makes a high divarication (average 155.4 ) between the posteriorly oriented digit III imprint. The high digital abduction clearly shows that digit I of the manus could be more hyper-extended anteriorly than previously thought: spreading the digits as much as possible would provide a more stable contact with substrate as well as better support the center of pterosaur body mass displaced anteriorly. The interdigital webbing of the pes imprint extends from the metatarso-phalangeal joint near to the bases of four claws. As these features clearly distinguish the Kitadani pterosaur trackways from five known ichnospecies of Pteraichnus, we assign them to a new ichnospecies, Pteraichnus nipponensis. Abundant small pterosaur ichnotaxa from Spain, Korea, and Japan indicate that many small pterodactyloid pterosaur species existed in the Early Cretaceous although there is no single skeletal datum yet.