Isao Iijima

was a Japanese zoologist known for his studies of sponges (Porifera) — including his circumscription of the genus Staurocalyptus — leeches (Hirudinea), flatworms (Turbellaria), birds, and fish. Professor of Zoology at Tokyo Imperial University, he is considered the founder of parasitology in Japan and was the first President of the Ornithological Society of Japan. and Ijima's leaf warbler.

Biography Born in Hamamatsu in 1861 into a samurai family of Hamamatsu Domain, at the age of fifteen he entered the in Tokyo, before enrolling as a student in the Science College at the Imperial University, Tokyo in 1878. Upon graduation in 1881, as one of three from the first cohort in the Department of Zoology, he became an assistant in the College. In 1903, he was involved in the establishment of and in 1904 he was appointed the second director of the . In 1912, he was the founding president of the Ornithological Society of Japan. In his personal life, Ijima enjoyed hunting, shooting, fishing, wine, and smoking a pipe. He died in 1921.