Glasswing

Greta morgane is an ithomiine butterfly in Nymphalidae. The glasswing taxon oto is treated as its subspecies in the Butterflies of America catalogue; Greta oto is another combination used for this taxon. [1][2]

In oto, transparent wing panels are crossed by dark veins. Black markings occupy the forewing tip and the end of the discal cell, while a white band crosses the outer forewing. The hindwing has brown edging beside its clear central panel. The sexes are similar. [3]

The subspecies oto occurs from Mexico to Panama. University field accounts place it at forest edges, clearings and stream margins, including secondary vegetation, at elevations of approximately 600–2,200 m. [3]

Females lay single white eggs beneath host leaves. Mature larvae have a pale green head with black spots and a green-white body with a yellow lateral stripe. The pupa has silver wing cases bordered by dark green lines. [3]

Field host records for oto include Cestrum lanatum and C. standleyi, both in Solanaceae; adults visit Inga flowers for nectar. Laboratory-reared glasswings in the transparency study developed on Cestrum nocturnum. [3][4]

Microscopy of laboratory-reared glasswings found narrow bristle-like and forked scales in transparent forewing regions, exposing more membrane than the broad scales of opaque regions. The membrane carries a lower layer of cuticular nanostructures and an upper layer of wax-based nanopillars. [4]

Removing the wax layer with hexane increased measured reflectance approximately 2.5-fold. The experiment establishes the anti-reflective role of the nanopillars on the clear membrane. [4]

Keep the enclosure closed and display it in indirect light, away from heat and damp conditions. Handle the frame by its edges and clean only its exterior according to the maker’s instructions.