In your ketucari's genotype, ray is denoted by the letters "nRy" (heterozygous) or "RyRy" (homozygous).
In its heterozygous form, ray has a pass rate of 45%. Homozygous ray has a 70% pass rate.
Color and Shape
As far as shape, ray can consist of a single line or a split end as seen in some of the examples above.
Ray must be a lighter color of your chosen base, with a minor deviation in hue. It can also be a fully desaturated color of the base, as long as it is lighter. Ray may be pure white.
These colors would be acceptable for this base color. They are either a lighter version of the base, or a lighter and desaturated version of the base. The last color on the right shows a minor deviation in hue, and is slightly more yellow than the base itself. Notice that this small change is not overbearing.
These colors would be unacceptable for ray. They are either darker than the base coat or have too drastic a hue shift.
Interaction with Other Markings
All markings can be layered under or over ray. It may even be somewhat transparent and bleach out the color of markings beneath it as seen below:
Ray can be influenced by segment.