A research group led by Natsumi Maruoka and Professor Jotaro Urabe of the Graduate School of Life Sciences, Tohoku University rediscovered "Mitsukuri Mijinko Daphnia mitsukuri", which was described as a new species in Japan in 1896 (Meiji 29), for the first time in 120 years. bottom.
Species identification of organisms was mainly performed by morphological characteristics, but with the development of genetic analysis in recent years, it has become possible to discriminate species that are difficult to discriminate by morphology by genome analysis.Research on mijinko in Japan has been carried out for a long time, and Mitsukuri mijinko was collected by Dr. Chiyomatsu Ishikawa, a professor at Tokyo Imperial University in 1896, and is the first Japanese professor of zoology at the Faculty of Science, Tokyo Imperial University. Tsukuri Kakichi) Named after Dr.However, after that, as taxonomy progressed in Japan, the existence of Daphnia pulexa was questioned and finally forgotten.
In this study, we performed genetic analysis and detailed morphological observation of individuals of Daphnia pulexa collected in Imba-numa, Chiba Prefecture.As a result, it was found that the Daphnia pulex collected in Inba-numa is different from the genetically known species, and the morphological characteristics are in good agreement with Dr. Ishikawa's description of Daphnia pulex. I concluded that there is.
This research reaffirmed the achievements of Dr. Chiyomatsu Ishikawa, a leader in the early days of zoology in Japan.Furthermore, an individual having the same base sequence as this individual has been found in China, and it is expected that biogeographical research on Daphnia pulexus in East Asia will progress in the future.
Paper information:[Zoo Diversity Web] Rediscovery After Almost 120 Years: Morphological and Genetic Evidence Supporting the Validity of Daphnia mitsukuri (Crustacea: Cladocera)
