The
holotype of
R. fergusonianus measures in total length (including tail), 40 times its width. The eyes are very small. The snout is acutely pointed. The body is longitudinally striated. It is blackish above, and the sides are white, dotted and spotted with black. The belly is white, with black dots and two series of large black spots, partially confluent into a zigzag band. The caudal disc is black and edged all round with yellow. ==Reproduction==