Key to species of Marganana (males only)

1. Pronotum and crown (DeLong & Freytag,1963: 259, fig. 2) moderately sloping anterad.Pygofer (DeLong & Freytag, 1963:261, fig.17) without apical process. Subgenital plate (DeLong & Freytag,1963:261,fig.16)with inner margin excavated.Style(DeLong & Freytag,1963:261, fig.15) whit blade short.Aedeagus (DeLong & Freytag, 1963: 261, figs.12, 13) with shaft moderately long and widened subapically, bearing pair of subapical processes arising far from apex. Distribution:North and Central America (Subgenus Marganana) ............................................................................................................................................. 2

— Pronotum and crown (Fig. 3) strongly sloping anterad. Pygofer (Fig. 7) with apical process. Subgenital plate (Fig. 8) with inner margin not excavated. Style (Fig.12) whit blade long.Aedeagus (Figs.13,14) with shaft long and slender,with pair of processes arising at apex or slightly subapically.Distribution:South America (Subgenus Declivana)..................................................................................................................................................................................................3

2. Forewing (DeLong & Freytag,1963: 259, fig. 1) with venation not reticulated. Subgenital plate (DeLong & Freytag,1963: 261, fig. 16) inner margin excavated near mid-length,apex slightly tapered.Style,in lateral view (DeLong & Freytag,1963:261,fig.14), very short,dorsal margin straight... M.suilla (Ball, 1935)

— Forewing(Gonçalves et al., 2021:88,fig.7A,B)with venation reticulated.Subgenital plate(DeLong&Freytag,1963:261,fig.10)inner margin excavated subapically, apex not tapered,rounded.Style,in lateral view (DeLong & Freytag,1963:261,fig.14), longer,dorsal margin excavated.... M.mexicana DeLong & Freytag,1963

3. Pronotum (DeLong & Freytag, 1963: 259, fig. 5) with several small black maculae near anterior margin. Pygofer (DeLong & Freytag, 1963: 261, fig. 23) apex bearing spine-like process.Style(DeLong & Freytag,1963:261,fig.20) with ventral margin of blade not produced subapically.Aedeagus (DeLong & Freytag, 1963: 261, figs.18, 19)with pair short apical processes,about one-sixth length of shaft..................................................... M.equata DeLong & Freytag,1963

— Pronotum (Fig.1) with four black spots.Pygofer (Fig.7)apex bearing rounded process with ventral margin serrated.Style(Fig.12)with ventral margin of blade produced subapically.Aedeagus (Figs.13, 14) with pair of long filiform subapical processes with half-length of shaft..................... M.tetramaculata sp.nov.