Gwyfyn heddiw yn rhywogaeth hardd o'r Mynyddoedd Creigiog y tu allan i Denver, Epermenia stolidota (Epermeniidae). Mae hyn mewn gwirionedd sbesimen mwy nag y mae'n ymddangos, am 20mm o wingtip i wingtip. Codwyd y rheiny, dywyll, tufts of scales on the posterior edge of the forewing is a great character for this family, as well as the stiff bristles on the hind tibia (also somewhat visible here). Mae 11 species in 2 genera in the United States, with likely a few more to be discovered. Fellow curatorial assistant David Bettman keyed this species out using the revision of the Nearctic species: PDF here.
