Tarucus is a butterfly genus in the family Lycaenidae. They are commonly known as blue Pierrots or simply Pierrots. The latter name is often used for the closely related genus Castalius. The delimitation of Castalius versus Tarucus is not yet fully resolved, with some species, such as the dark Pierrot (T. ananda), having been moved between the two genera repeatedly. It may even be that they are eventually regarded as synonymous, and in that case the older name Castalius would supersede Tarucus by the Principle of Priority.
Several species formerly in Tarucus were moved to Leptotes, another closely related lineage (though not quite as close as Castalius).
The caterpillars of this genus typically feed on Zizyphus and are attended by ants.
