mostly Ithomiine butterflies. Some authors consider
the group a subfamily (Ithomiinae) whereas, others
regard them more as a tribe (Ithomiini) of the nymphalid
subfamily Danainae.
They are indeed diverse and the evolutionary success of
these butterflies (blending-in -- in plain sight) via minimal
markings and transparency also, carries over to other unrelated
familes/subfamilies of butterflies.

Many moons ago I had the priviledge of visiting Bolivia for
a 2 week stay on a lepidopterists excursion led by Tom
Emmel. It was wonderful meeting like-minded enthusiasts
with the same passion/joy for insects. Butterflies abounded
so it was not easy to stay focused on any (one) group but, I
tried to "stay sharp" about glasswings.


All told, I probably encountered some 10 or 12 species
myself however, I'm certain there were others. Some species
were more commonly encountered than others whilst some
were just "one and done" singles....
Some butterflies encountered from differing genera AND
perhaps other subfamilies/families (such as the next two);
possessed the same blending-in abilities but, were not TRUE
ithomiines like the first 3 posted above.


So, in a sense the term "glasswing butterfly" can actually
cover a broad scheme of butterflies if one remains open minded.