Blue ghost
Phausis reticulata
Also called: Blue ghost firefly
At a glance
- Flash
- A steady blue-white glow held for up to a minute — not a blink — as the male drifts low
- Habitat
- Moist, undisturbed hardwood forest floor and leaf litter
- Range
- The southern Appalachians, southeastern United States
- Season
- A few weeks in late spring to early summer
- Size
- ~7–8 mm
- When active
- Full darkness, drifting low through the forest
Overview
The blue ghost is unlike almost any other firefly. Rather than blinking, the males hold a steady, eerie blue-white glow for up to a minute at a time as they drift slowly, ankle-high, through dark hardwood forests. Seen in numbers, they look like a field of tiny lanterns floating through the trees.
As with the glow-worm, the females are larviform and wingless, glowing faintly from the forest floor and leaf litter. The species is extremely particular about its home — old, undisturbed, moist forest — and famously sensitive to light and foot traffic, which is why the best-known viewing sites now restrict flashlights during the season.
How to identify
A steady, drifting blue-white glow low in the forest — quite different from the yellow blinks of other species. It needs genuine darkness, so it vanishes near any artificial light.
Conservation
Exceptionally sensitive to light pollution and trampling. Popular viewing areas now ban white flashlights and keep visitors to trails; keeping its forests dark and undisturbed is everything.
Sources & further reading
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