Seto Marine Biological Laboratory (SMBL) is located on the western coast of Kii Peninsula in central Japan. A branch of Kuroshio Current is primarily responsible for the warm, but mild climate in this region. The topography around the SMBL is complex and includes steep cliffs and many embayments. Sunken rocks and small islands are scattered around the region. The substratum is diverse and ranges from bare rock to mud, gravel and coarse sand. These settings provide a diverse range of habitats for the marine fauna found around the SMBL. The SMBL has had a long history of marine invertebrate zoology research, including developmental biology, ecology, taxonomy and phylogeny. Professor Takasi Tokioka (1913-2001) studied taxonomy and phylogeny focusing primarily on ascidians and arrow worms at SMBL for about 40 years and was an internationally recognized expert on marine invertebrates. In this paper, we offer a historical retrospective on his life and research. Traditionally, short training courses for marine biology of universities around central Japan are held in SMBL every year. These courses are diverse and range from taxonomy, and molecular phylogeny, to embryology, ethology and physiology. A review of 15 marine courses from fiscal year 2012 revealed that taxonomy was included in all marine coursework. In this paper, we discuss the importance of taxonomy for zoology and other disciplines.