What is quite unusual and interesting in this case is that a number of Z. mahaindividuals in Fukaura exhibited unique color-pattern modifications on the ventral side of their wings (Fig. (Fig.2).2). In 2000 and 2001, the proportion of these modified individuals was estimated to be less than 2% (only a few modified individuals were caught), all of which showed slight modifications (Fig. (Fig.1C).1C). In 2002, the percentage of the modified individuals increased to 15% (35 modified individuals out of 230 caught), including individuals with slight modifications. In 2003 and 2004, the percentage of modified individuals was estimated to be similar to the amount seen in 2002, many of which exhibited small degree of modifications. However, despite excluding the individuals with small degree of modifications, the percentage of modified individuals reached 9.7% (29 severely modified individuals out of 300 caught) in 2003.