Opsigalea Hampson

Opsigalea Hampson, 1906, Catalogue of the Lepidoptera Phalaenae in the British Museum, 6:84.

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.

This genus appears, despite the vast superficial dissimilarity, to be closely related to the previous genus, Dolocucullia. I am inclined to believe that these two genera are neotropical derivatives of the ancestoral line that gave rise to Cucullia despite the differences between them and Cucullia. I base this belief on tympanaic structure and the superficial similarities of Opsigalea and Cucullia. Admittedly superficial similarity can be misleading, but in the absence of contradictory evidence, it is better than nothing.

The distribution of the species of Opsigalea is unusual. There are two species in Mexico and Central America in addition to the Texas species Opsigalea blanchardi; Opsigalea ocellata (Walker) and Opsigalea phocylides (Druce). These three species are separated by a large distributional hiatus from an undetermined number of species in southern South America, but including Opsigalea hildana (Schaus), Opsigalea perlucida (Jones), and Opsigalea prima (Köhler).

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.