Soki Hattori

Fukui Prefectural University · Institute of Dinosaur Research

The isolated fossil remains of an allosauroid theropod from the Lower Cretaceous Khok Kruat Formation of Khorat, Thailand, are described in this study. Detailed observations support the establishment of a new allosauroid, Siamraptor suwati gen. et sp. nov. This new taxon is based on a composite cranial and postcranial skeleton comprising premaxilla...

Archosaurs displayed an evolutionary trend toward increasing bipedalism in their evolutionary history, that is, forelimbs tend to be reduced in contrast to the devel- opment of hindlimbs becoming major weight-bearing and locomotor appendages. The archosaurian locomotion has been extensively discussed based on their limb morphology because the latte...

Spinosaurids are large-bodied theropods exhibiting unusually narrow jaws with characteristic conical teeth commonly regarded as an adaptation for piscivorous diet. Despite rare occurrences of their bone materials, spinosaurids are widely known from the Jurassic to Cretaceous of both Gondwana and Laurasia mostly based on the teeth. Among them, Asian...

A bizarre coelurosaurian theropod Fukuivenator paradoxus is known only from the holotype specimen preserving majority of the skeleton from the Kitadani Dinosaur Quarry of the Lower Cretaceous Kitadani Formation, Tetori Group, Fukui, Japan. With aids of computed tomography techniques, a re-examination of the holotype specimen reveals additional feat...

The morphology of the neurovascular canal in the jaw has been analysed in several fossil reptiles, including theropod dinosaurs. However, the details of the neurovascular canal in the dentary of theropods have not been fully elucidated. In this study, we described the well-preserved dentary of Tyrannosaurus rex, analysed the morphology of the neuro...

We here report an ankylosaurian ilium from the Albian–Cenomanian Longjing Formation of Yanji City, Jilin Province, northeastern China. The diagnostic features allowing referral of this specimen to Ankylosauria include: an ilium rotated horizontally dorsal to the acetabulum with the primitive lateral surface facing ventrally; long and laterally dive...

The new deinonychosaur trackway was recovered from the lower Upper Cretaceous Jinhua Formation of Zhejiang Province, southeastern China. This trackway includes nine well-preserved tracks characterized by elongate and didactyl morphology, and thus is assigned to the ichnospecies Velociraptorichnus sichuanensis. This trackway enables more accurate es...

Carcharodontosauria is a clade of theropods with a wide distribution in Laurasia and Gondwana from the Late Jurassic to the Late Cretaceous. However, carcharodontosaurs have been poorly known so far in the Early to mid-Cretaceous of Asia. For the first time, a definitive carcharodontosaurian theropod is established from a series of autapomorphies a...

Two mysticete fossils were found during construction of Mizunami-Kita Junior High School, Mizunami, Gifu, Japan in December 2016 and March 2017. This paper is a preliminary report of the fossils (MFM18127 and 18128). MFM18128 was recovered from the Yamanouchi Member, Akeyo Formation, Mizunami Group and includes cervical and thoracic vertebrae and r...

Fish otoliths, teeth and a fin spine are found from the lower Miocene Akeyo Formation of the Mizunami Group at the construction site of Mizunami-Kita Junior High School in Toki-cho, Mizunami City, Gifu Prefecture, Japan. The otoliths of Pterothrissinae gen. et sp. indet., Nemipterus sp., ?Gobius sp., Gobiidae gen. et sp. indet., Soleidae gen. et sp...

The emergence of a reversed hallux (first pedal digit) in the theropod lineage is regarded as an important indicator of increasing grasping ability and possibly arboreality. However, functions of the pes with a plesiomorphic, non-reversed hallux in non-avian theropods, other than the major role in supporting and propelling the body during the stanc...

We attempted to produce the transparent dinosaur skull models by resin molding at low cost, which allows us to see the internal structure of the skull. Since multiple transparent models can be made in a short time after the production of the mold, it holds promise for expanding range of application of the transparent model in research and education...

New material of a troodontid theropod from Khamaryn Ar in Mongolia, representing the second troodontid specimen described from the Lower Cretaceous of the Gobi Basin, is reported. This material consists mainly of caudal, manual and pedal bones, and can be assigned to Troodontidae based on the presence of derived features such as distal caudals bear...

Theropod dinosaurs including birds have four pedal digits, and some of them acquired grasping function, which is generally considered as relevant to arboreality and hunting ability. Although a reversed pedal digit I of birds clearly indicates their grasping ability, functional diversity of the pes of non-avian theropods possessing a non-reversed di...

Most theropods have four pedal digits, and their grasping function is relevant to arboreality and/or hunting ability. Although an opposable digit I (hallux) in birds clearly indicates their grasping ability, functional diversity of the pes in non-avian theropods possessing a non-reversed hallux has not been fully explored. To clarify pedal function...

The presence of an opposed hallux (digit I) in theropod lineage is regarded as an important indicator of increasing perching ability. However, the function of the foot with non-reversed hallux of non-avian theropods is poorly understood so far. To clarify the foot function of non-avian theropods, principal component (PC) analyses were conducted on...

Among the four pedal digits of non-avian theropods, only pedal digit I (hallux) could not reach the ground mainly because of its size relative to other digits. The presence of an opposable hallux is regarded as an important indicator of increasing arboreality because it had a crucial function in perching ability. There are, however, only a few stud...