New Species

Japanese geologists and biostratigraphers commenced work on radiolarian fossils at around the same time in the late 1970's in an explosive, so to speak, fashion by utilizing the scanning electron microscope (SEM). Prof. K.Nakaseko of Osaka University, Prof. K.Ichikawa of Osaka City University, and Prof. S.Mizutani of Nagoya University played leading roles in this new trend of research works. One of the notable papers in those days was a short report dealing with the occurrence of Jurassic radiolarians in the Mino area published by the Japan Academy (Mizutani et al., 1981). In early stages of our studies, however, we carried out many field investigations covering lithostratigraphy, biostratigraphy and chronostratigraphy together with paleontological works, because most of our data seemed to be strange and novel. As a result, some new species had to be described, and they were used in our discussion of the age assignment as well as the geological history of the Japanese Islands. Several papers listed in this database have disclosed the occurrence of new species of Radiolaria and they described the fossils from the paleontological point of view. Almost all of them have been really regarded as significant new species and are used as key taxa for age determination of the strata which yielded them; in fact, some of these species are now cited as international key species by Baumgartner (1995).