Thick-tipped Greta (Great oto)
The Glasswings are some of the most exquisite looking butterflies in Costa Rica, the Thick-tipped Greta being the most common of the twenty or so Glasswings that range throughout the country. Commonly kept in butterfly gardens, this species is also just as frequently seen in the wild, including in gardens of San Jose.
Glasswing butterflies can be identified as Glasswings by virtue of their distinctive, transparent wings. Resembling panes of glass, these living jewels are reminiscent of the thinly cut, transparent crystals sometimes used in wind chimes, or of the crystals one would expect to see on a necklace or earrings. On the Thick-tipped Greta, note the white and orange markings near the tips of the wings. Although identification to species can be very difficult due to the presence of other, extremely similar Glasswing species, if you see a Glasswing butterfly in the garden of your San Jose hotel, it is almost certainly a Thick-tipped Greta; the most common Glasswing butterfly in Costa Rica.
Behavior in Costa Rica
The Thick-tipped Greta frequents the dim understory where it can take full advantage of its transparent wings since they are more noticeable and less transparent in full sunlight. It makes short, quick flights through the understory in search of flowers of a variety of plants, often resting with its wings held upright, the background clearly visible through the clear wings. This is a species that also undertakes altitudinal migrations, moving upslope to humid forests during the dry season on the Pacific slope. At such times, it can become locally abundant.
Habitat and distribution in Costa Rica
The Thick-tipped Greta is a very common butterfly species likely to be encountered in well shaded gardens in San Jose and other disturbed habitats of lowland and middle elevations of the Pacific slope. It is most common in middle elevations and is very rare on the Caribbean slope.