Recondite

Hidden from sight. Also, difficult or impossible for one with ordinary understanding or knowledge to comprehend.

The Cannibal Galaxy, page 69.

Recondite to any human eye, the pigments in the plants and flowers reflect high-energy ultraviolet light, this invisible yet shouting shine lures on the sensitive bee, it lights in the belief it wills to light, when the truth is it is being drawn on by the paradisal fragrances of the secret sugar compounds that ambush it amid nectar and pollen.