The toxic effects of snake venom of Tokara Habu (Trimerusurus tokarensis) were tested injecting serially diluted venoms intramuscularly into the legs of mice. The hemorrhagic lesion occurred at the minimum amount of 2γ of the venom and the mld was about 600γ which seemed that the venom was less toxic than that of T. flavoviridis or Agkistrodon halys. As the results of cross test of antivenins of T. tokarensis, T, flavoviridis and A. halys, some instances of cross-protection occurred although heterologous antivenins were less effective than homologous antivenin in protecting mice against effects of venom injection.
Thus, the venom of T. tokarensis was neutralized by antivenin of T. flavoviridis, and vice versa. The hemorrhagic activity of the venom of T. tokarensis was also protected though in low degree by the antivenin of Agkistrododn halys, and vice versa.
Snake bite cases on Tokara Island were not so serious as that of Trimeresurus flavoviridis found in Amami Islands. There was no severe necrosis or lethal cases. Those facts indicated that the amount of the venom injected in a snake bite case is smaller and low toxic and the snake is not so aggressive as that of Habu snake.