The neon in neon blue platy refers to a reflective sheen in the scales of the fish. In general "neon" when used with platies refers to this sheen.

The Blue Neon Platy (Xiphophorus maculatus) is a colorful platy variety that boasts a reflective sheen in the scales. This fish is an omnivore, so it will potentially prey on smaller dwarf shrimp and their fry, but it is otherwise safe to keep with peaceful invertebrates as well. This fish is not a picky eater and it will accept a variety of high-quality dry foods, but these should be supplemented with a variety of frozen foods. Living up to 3 years and reaching about 2 inches the platy is a great community fish.