Trifurcula bupleurella is a moth of the Nepticulidae family. It is found in southern France and the Iberian Peninsula.
The larvae feed on Bupleurum fruticosum and Bupleurum rigidum. They mine the leaves of their host plant. The mine consists of an upper-surface, whitish corridor. It is narrow at first, but considerably widening later. The frass is deposited in a thin black central line. Some mines are contorted and confined to a limited space, others follow a vein and are quite long.
References
Trifurcula bupleurella Wikipedia(Text) CC BY-SA