Species · GBIF taxon 6990480
Genji Firefly
Luciola cruciataAlso known as Genji-botaru, Genji Lightning Bug
Genji fireflies illuminate Japanese stream banks during early summer nights with a slow, synchronized rhythmic flashing. The aquatic larvae live in clean, running water where they hunt freshwater snails before pupating in the damp soil nearby. These beetles hold a deep cultural significance in Japan, celebrated in annual viewing festivals and serving as indicators of healthy, unpolluted freshwater ecosystems.
NocturnalBioluminescentAquatic Larvae
Licensed reference(c) Alpsdake, some rights reserved (CC BY-SA) · cc-by-sa
—observations
—countries
—peak records
Not EvaluatedConservation statusIUCN Red List categoriesLCNTVUENCREWEXNot Evaluated — not placed on the risk ladderRed List categories, explained →
Diet & prey
- Freshwater snails
- Small aquatic invertebrates
Predators
- Frogs
- Spiders
- Bats
ThreatsWater pollution, river channelization, and light pollution
HabitatsClear streams, irrigation ditches, and wet paddy fields
Life span1 to 2 years
Size / weightNot available
Classification
- FamilyLampyridae
- SpeciesLuciola cruciata
Range data is not available yet.
Interaction riskLow
- Low
- Moderate
- High
- Very high
- Why interaction risk is low
- Safe to observe at a normal distance.
- What to notice
- Look for large beetles with a black cross-like mark on a pinkish-red pronotum flashing green-yellow light.
- Support conservation
- Never capture wild adults or disturb stream margins where larvae and pupae develop.
Responsible observation
- Avoid artificial light: Turn off flashlights and phone screens to prevent disrupting their mating flashes.
- Watch the weather: Look for them on warm, humid, windless nights after rain for the most active displays.
- Protect stream banks: Keep to designated paths to avoid crushing pupating larvae in the riverside soil.
Distant Cousin (c) Katja Schulz, some rights reserved (CC BY) · cc-by
Primary Prey (c) Saryu Mae 前 朝琉, some rights reserved (CC BY), uploaded by Saryu Mae 前 朝琉 · cc-by
Close Relative (c) http://www.flickr.com/photos/yellow_bird_woodstock/, some rights reserved (CC BY-SA) · cc-by-sa
Image unavailableClose Relative
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