Late Pliocene Plant Biostratigraphy of the Lowermost Part of the Osaka Group, Southwest Japan, with Reference to Extinction of Plants.

Stages of major floral change in Japan based on macrofossil evidence and their connection to climate and geomorphological changes since the Pliocene

“…(For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.) (Momohara, 1992). Because thermophilous plants, with a northern distribution limit in the warm-temperate zone, were accompanied by such cool-temperate trees, Momohara (1992) ascribed the increase of cool-temperate trees to mountain uplifts along the southern part of the basin.…”

“…The fossil assemblages of this stage are dominated by warmtemperate conifers that are now extinct from Japan, such as Cunninghamia, Glyptostrobus, Metasequoia, Sequoia, Taiwania, Keteleeria, Pseudolarix, and Nothotsuga longibracteata (Momohara, 1992(Momohara, , 2011. Broad-leaved trees, whose modern relatives are limited to the southern part of the warm-temperate and subtropical zones (defined by Kira, 1991), such as Quercus chenii, Paliurus nipponicus, Fortunearia, Reevesia, Choerospondias, and Melliodendron, are common elements of the assemblages.…”

“…The decreasing exotic and thermophilous elements were accompanied by the appearance of conifers that prevail in modern Japanese vegetation, such as Abies, Tsuga, and Pinus subgen. Diploxylon, in the Osaka Group (Momohara, 1992).…”

“…3; Momohara, 1992Momohara, , 2010, is dated between ca. 3.6 and 3.35 Ma based on widespread tephra beds (Satoguchi and Nagahashi, 2012).…”

“…Their ages have been determined based on magneto-and tephrostratigraphy in a coastal basin along the Sea of Japan in the central Niigata Prefecture, and in inland basins surrounded by mountain ranges in west Fukushima Prefecture, the central Kinki District, and central and south Kyushu Island. Among these, the finest plant biostratigraphy was developed in the Kinki District based on assemblages obtained by sieving sediments (Momohara et al, 1990;Momohara, 1992), whose age control was provided by correlation to many widespread tephra beds (Fig. 2;Satoguchi and Nagahashi, 2012).…”