Pentalagus furnesii

Bone histomorphology is an effective method for species identification of fragmentary osseous remains. The 1997e1998 excavations of the Kashiwadai 1 Upper Paleolithic site (ca. 22e20.5 kyBP) in Hokkaido (the northern island of the Japanese Archipelago) yielded tiny bone fragments, which had been burned to white and broken into pieces less than 1 cm in size, making their species identification by gross morphology alone impossible. For the purpose of species identification, histomorphological analyses were performed on thin sections of the Kashiwadai 1 bone fragments. Compact bone cross sections taken from medium-to large-sized land mammals in the Pleistocene and Holocene Hokkaido were prepared for comparison. The structures of the Kashiwadai 1 samples consisted of secondary osteons and plexi-form bone. Consideration of the presence versus absence of plexiform bone and quantitative assessments of osteon sizes and bone cortical thickness allows for distinction between medium-sized deer, large-sized artiodactyls, small-to medium-sized carnivores, large-sized carnivores, elephants, and humans. The histomorphological characteristics of the Kashiwadai 1 samples were quite similar to those of both sika deer and ancient sika deer. A probable conclusion is that medium-sized deer was the primary game hunted by Paleolithic people at the Kashiwadai 1 site. Interestingly, the samples did not include elephant or large-sized artiodactyls, which were the predominant species in other Paleolithic sites of the Japanese Archipelago. This is the first evidence of human hunting medium-sized animals in the Upper Paleolithic period of the Japanese Archipelago based on faunal remains.

Windows into sauropod and synapsid evolution. Essay in honor of Prof. Louis L. Jacobs., 2023

ABSTRACT Reported here is the discovery of a new species of leporid mammal from the Pliocene Kobiwako Group in cen- tral Japan. Pliopentalagus okuyamai, sp. nov., is described based on a partial skull and upper dentition alone. In case of extinct Leporidae, no taxon has been described without the lower dentition, especially the lower third premolar. However, Pliopenta- lagus okuyamai can be distinguished from all known extant and extinct genera (except for Pliopentalagus) by characteristics of the palatal bridge and upper dentition alone. Among the genera of the Leporidae, Pentalagus furnessi is most closely related to Pliopentalagus. However, the extremely deep secondary enamel folds of the internal reentrant and the more squared outline of upper molariform teeth in Pentalagus furnessi can be easily distinguished from Pliopentalagus. Although the genus Azt- lanolagus may be congeneric with Pliopentalagus, A. agilis can be distinguished by the much shallower depth of the second- ary enamel folds of upper molariform teeth and much smaller size than Pl. okuyamai. Among the known species of Pliopentalagus, Pl. okuyamai is distinguished by its largest size, the deepest and most densely arranged secondary folds, and the largest length/width ratio of the palatal bridge. Pl. okuyamai is the first and oldest record of the family Leporidae in Japan, and may be a possible ancestral form of, or most closely related to, Pentalagus furnessi.

Oryx, 2000

2015. New fossil remains from the Pliocene Koetoi Formation of northern Japan provide insights into growth rates and the vertebral evolution of porpoises. Acta Palaeontologica Polonica 60 (1): 97-111.

2008

We describe a fragmentary tooth of a rhinocerotid perisso-dactyl recovered from the middle unit of the upper Miocene Oiso Formation, Japan. Although the specimen is fragmen-tary and heavily worn, it is worth describing because the

Tropics, 2000

Results of present studies on the stratigraphic levels and the paleontological analysis of tenestrial vertebrate fossils in the Ryukyu islands fumish valuable clues and considerations as to the history and age of animal migration from the continent to its neighboring islands. To date, four diagnostically different stratigraphic levels containing Late Miocene to latest Pleistocene vertebrate fossils have been delineated in the islands. Geotogical and paleontological data suggest that the area of the Ryukyu Islands has been repeatedly connected to the Asiatic Continent and each land connection has been followed by migration of characteristic terreshial vertebrates from the continent. Among the fossil assemblages found in these four different stratigraphic levels, those from lrvel 2 @arly Pleistocene) are known to occur in shallow marine deposits underlying the Early to Middle Pleistocene Ryukyu Group. They are considered to be immigrants from either the latest Pliocene Renzidong fauna (Jin & Zheng, 1.998; Huang, 1998; Jin et at., 1999) in Anhui Province or the Wushan hominid fauna (Iluang et al., 1991) in Sichuan Province, both located in Central China, during the second land connection. This assemblage may be regarded as the oldest post-Miocene fauna and might include the ancestors of the Pleistocene fossil and living endemic terrestrial vertebrate faunas of the Ryukyu islands. Another important species of fossil assemblage of terrestrial vertebrates in the islands is closely associated with the latest Pleistocene fissure and cave deposits developed within the Ryukyu Group or coeval tenace deposits (Irvel 4). These assemblages are considered to be mixed faunas that migrated from the Asian mainland to the islands during different periods of land connection in the past. Tenestrial vertebrate fossils from this level include large mammal (deer) and giant tortoise that became extinct at the end of the latest Pleistocene. However, descendants of other animals including mammals, amphibians and reptiles, are still living in the islands forming characteristic insular endemic fauna.

2002

Journal of Vertebrate Paleontology, 2006

Journal of Vertebrate Paleontology, 2011

Anthropological Science, 2001