found it, they are known as glasswing butterflies (Greta oto).
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Greta oto is a brush-footed butterfly, and is a member of the clearwing clade; its wings are transparent. Its most common English name is
glasswing, and its Spanish name is
espejitos, which means "little mirrors." Indeed, the tissue between the veins of its wings looks like glass. It is one of the more abundant clearwing species in its home range, which extends throughout Central America into Mexico. The opaque borders of its wings are dark brown sometimes tinted with red or orange, and its body is dark in color. Its wingspan is between 5.5 and 6 cm.
Glasswing butterfly, Greta otoAdults inhabit the rainforest understory and feed on the nectar of a variety of tropical flowers.
G. oto prefers to lay its eggs on plants of the tropical nightshade genus Cestrum. The silvery-gray caterpillars feed on these toxic plants and store the alkaloids in their tissues, making them distasteful to predators such as birds. They retain their toxicity in adulthood. The same alkaloids that make them poisonous also are converted into pheromones by the males, which use them to attract females.
G. oto adults also exhibit a number of interesting behaviors, such as long migrations and lekking among males.
