A Wood Bokuto Carved as the Sansukumi by Masanao of Ise
Most of the shaft of the bokuto is formed by the body of the snake, the tail turning back on itself. A toad climbs upwards watching a companion fight valiantly to escape from being devoured while a slug seems to be avoiding the issue. The eyes of the snake are double inlaid, the pupils of the toads are of dark horn.
While the signature is a little weak, the mouth of the snake is typical of the school, so on balance I stand by the attribution