Key to species of the mediseorsa group of the genus Nemophora Hoffmannsegg

1. Forewing without basal black speckle, outer fascia narrowed medially (Fig. 1).................. N. mediangusa sp. nov.

- Forewing with basal black speckle, outer fascia separated medially............................................. 2

2. Digitate process arising from middle between base of costa and transtilla; phallus with banded process arising from distal 1/3 (Fig. 8)............................................................................. N. longiuga sp. nov.

- No process present between base of costa and transtilla; phallus without process................................... 3

3. Uncus with papillary process posteromedially; vinculum 4.3 × length of valva (Fig. 9)............. N. longissima sp. nov.

- Uncus without papillary process posteromedially; vinculum 2.5 × length of valva (Fig. 10)........ N. mediseorsa sp. nov.