Large for a
Photinus. Blackish-brown finely, densely rugose (wrinkled) elytra, side margins and suture of elytra yellow. Pronotal disk pinkish with a black spot. Pronotum convex. Underside: Ventral abdominal segments six and seven large and occupied by light organ in male. Abdominal sternites of male have distinct
(2). Female flightless
(3), or "seldom" flies, as it does have normal wings
(4).
Flash is distinctive: male hovers about two feet (0.6 m) above ground, then drops vertically, gives single prolonged flash as is ascending, then flash diminishes
(2). Flashing occurs at dusk, earlier in evening than most other fireflies.