Flabellina Nudibranch

The cave walls of Budva's Blue Cave host dense colonies of this vivid purple and orange nudibranch, grazing on the hydroids that thrive in the dim, nutrient-rich interior water. Flabellina affinis derives its striking colouration from the cnidocysts of the hydroids it consumes, incorporating unfired stinging cells into its own cerata as a chemical defence. They are among the most reliably located subjects for macro photographers in Montenegro.