"Pelucas" or "lucas" is a Mexican candy powder in a little plastic jar; it's salt and powdered sugar and hot chili spice and some kind of sour or acid stuff too, like lime flavoring. Kids buy it from ice cream trucks and eat it plain, but it is also meant to be dusted onto vegetables or fruit.
The word literally means "wigs" but I have no idea why the sweet/sour/hot powder is called that.