Red, pink or yellow means the square could do with some more attention (often these are squares on the county boundaries, and some would be filled in if the Oxfordshire data was added to the map).
Red square = up to 100 species
Pink square = up to 200
Yellow square = up to 300
Blue square = up to 400
Green square = up to 500
White square = the square in which Steve Nash used to trap! (506 species)
View Macro-moth species per 10km square in a larger map