Spurilla neapolitana
This species has an amazing color variation. People think that these sea slugs come in such a wide range of colors because they eat a wide range of things, and you are what you eat. The food they eat gives them color.
Feeding animals different foods can be used as a method of marking. For example abalone shells can be marked by feeding the animals different algaes in different order as they are growing. This will give you colored bands in different orders which can help in identification of individuals.
The specimen on the right was identified by Yolanda Camacho.
