We report occurrences of carnivorans from the Irrawaddy beds in central Myanmar. Intensive expeditions in the recent decade improved understandings on biostratigraphic position of each fauna within the Irrawaddy beds (Late Miocene to Early Pleistocene) and brought out discovery of carnivoran specimens. An amphicyonid has been collected from the Tebingan locality, near the basal horizon (Late Miocene) of the Irrawaddy beds. This large animal is considered to be a new genus endemic to Myanmar. The Chaingzauk fauna (around the Miocene/Pliocene boundary) yields the most abundant remains: An ailurid (Simocyon), a large ursid (Agriotherium), a saber-tooth felid (Homotherium), at least three species of hyaenids including a primitive subfamily member (Ictitherium), a running form (Hyaenictis), and a wolf-like form (Hyaenictitherium). The fauna consists of medium to gigantic forms; sampling biases seem to influence collection of carnivorans as well as those of other mammals. All of these carnivoran genera have cosmopolitan distributions, and the occurrences from Myanmar fill their geological gap at Southeast Asia within Eurasia. Additionally, an indeterminate feliform was collected from the fauna. The Gwebin fauna (Late Pliocene) include a herpestid (Urva), a medium-sized felid, and a viverrid (Viverrinae). This first record of herpestid in the Pliocene of Asia confirms that the extant Asian mongoose lineage had already dispersed into Southeast Asia from South Asia by the Late Pliocene. Postcranial materials from the Sulegon area (Pliocene) provide evidences of additional taxa, a small felid and a large hyaenid. These recently collected carnivoran specimens revealed presence of diverse carnivorans from the Irrawaddy faunas. They fill geographical and/or chronological gaps of carnivoran distributions in Southeast Asia. Furthermore, the comparisons among carnivoran assemblages indicate faunal turnover of carnivorans at the family or subfamily level from the Late Miocene to the Late Pliocene of Myanmar.

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This paper provides a comprehensive review of prior research related to the palaeogeography and topography of the Japanese archipelago, the transition of the strait west of Kyushu, and the transitions in flora, which are considered significant factors influencing the formative process of land mammals in Japan. The study summarizes the fossil records of terrestrial mammals from the Cenozoic era in Japan, excluding the Ryukyu Archipelago, and outlines the formative processes associated with these fossils.To comprehensively understand the evolution of terrestrial mammals in Japan during the Cenozoic era, it is essential to consider four key periods: (1) the Continental Period (prior to 20 million years ago), (2) the Island Period (approximately 20 to 15 million years ago), (3) the period of migration from the continent and subsequent expansion within the archipelago (approximately 15 to 3 million years ago), and (4) the period of formation of modern mammalian fauna (from approximately 3 million years ago onwards). Notably, the present-day terrestrial mammal fauna in archipelagic Japan were formed approximately 1.7 million years ago.

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