Alesa is also a feminine given name meaning "great happiness."Alesa is a New World (Neotropic ecozone) genus of metalmark butterflies found in northern South America.This genus is distinguished by a vast sexual dimorphism receding somewhat only in one species. The body is slender, the head is broad and slanting,with a flat forehead and closely appressed short palpi. The antennae are very long, only slightly thickened at their ends.