Opsigalea is an enigmatic genus. The species in the genus look
like members of Cucullia, but there are significant morphological
differences. The costa of the forewing is bent downward at the apex giving
the forewing a distinctly rounded appearance. The male vesica is characterized
by an absence of distinct spines, as found in Cucullia, and their
replacement by one or more sclerotized patches as in Dolocucullia.
The ductus seminalis arises from the top of the bursa, not the bottom
as in Cucullia. Specifically it is the appendix bursae that is
absent, not the corpus bursae. On the other hand the external and internal
tympanal structure is essentially the same as in Cucullia.
The larvae of all known species are unknown. However the Mexican species
Opsigalea ocellata has been reared from Buddleja sessiliflora,
a shrub or small tree in the family Loganiaceae.