# Firefly (*Photinus pyralis*)

Fireflies, or lightning bugs, are special insects that light up at night. They use their glow to attract friends and find mates!

- **Category:** [Insects](https://www.snappit.app/explore/categories/insect)
- **Rarity:** Common
- **Danger:** 0/5 · No known danger
- **Snaps:** 35
- **Habitat:** Fields, meadows, lawns and woodland edges, even in towns and cities.
- **Also known as:** Lightning Bug

![Firefly](https://res.cloudinary.com/drieglelr/image/upload/v1771438745/objects/5492.jpg)

## Appearance

The Firefly is a nocturnal beetle with a soft body, typically dark brown or black, often featuring yellow or reddish markings on its pronotum. Its most distinctive feature is the pale, light-producing organ usually found on the underside of its abdomen, making it easily recognizable.

## Taxonomy

- **Kingdom:** Animalia
- **Phylum:** Arthropoda
- **Class:** Insecta
- **Order:** Coleoptera
- **Family:** Lampyridae
- **Genus:** Photinus

## Firefly, up close

The common eastern firefly, or big dipper firefly (Photinus pyralis), is a soft-bodied beetle of North America east of the Rocky Mountains and one of the continent’s most familiar fireflies. On early-summer evenings males flash yellow-green light while swooping upwards in a J shape, and females answer from the grass. Its larvae glow too and live in and under the soil, where they hunt earthworms.

Also called: Common eastern firefly, Big dipper firefly, Eastern firefly.

A 0.3-second flash, a J-shaped swoop and an answer from the grass 2–3 seconds later. Spin it, tap it, then test yourself.

### Special abilities

- **Big Dipper** (J shaped flash path): A searching male flies low, dips, then climbs steeply while he flashes, so his light draws a J in the dusk. [3][2][10]
  - The dip-and-climb flash is the trademark of this species and gives it the name “big dipper firefly”.
  - Scientists collecting fireflies for the 2018 genome study picked out males by their “rising J” flash.
  - Other fireflies in the same field draw different shapes and rhythms, which helps females tell species apart.
- **Light Code** (≈0.3 s male flash): Each male gives one short flash, about 0.3 s long, and repeats it every 5–10 s while he patrols. [3][10][11][12]
  - The 35 described Photinus species in North America each have their own on-off timing of flash length and gap.
  - Scientists think nitric oxide gas helps switch the lantern on, by letting oxygen reach the light reaction for a moment. The exact switch is still being studied.
  - On a busy evening a field can twinkle with many males flashing at once.
  - Light-talk timing: Male flash ≈0.3 s; Female’s wait before answering 2–3 s; Gap between a male’s flashes 5–10 s
- **Grass Reply** (2–3 s answer delay): A female perched in the grass twists her abdomen towards a male’s flash and answers with one flash 2–3 s later. [3][4]
  - Her answer, and its timing, is part of the species code, so the male can tell she is a common eastern firefly.
  - He flies towards her, and they swap flashes as he homes in.
  - Females choose between males, and in Photinus the flash signal matters to that choice.
- **Light Factory** (41% reactions that make light): Light cells in the lantern mix luciferin, the enzyme luciferase, ATP and oxygen. About 41% of the reacting luciferin molecules give off a particle of light. [3][7][13][9]
  - Old books say firefly light is nearly 100% efficient. A 1959 measurement gave 88%, but a careful re-measurement in 2008 found about 41%.
  - That is still far more efficient than luminol, a glowing chemical used in labs, at about 0.012, or 1.2%.
  - Oxygen reaches the light cells through a dense brush of tiny air tubes.
  - Light from each reaction (quantum yield): Firefly, measured 2008 41%; Firefly, old 1959 figure 88%; Luminol (lab glow chemical) 1.2%
- **Warning Glow** (2 spots larval lights; still debated): The larva glows from two small spots near its tail end. Its glow rises and falls slowly instead of flashing. [3][7][14]
  - Scientists think larval glow is mostly a warning to predators that the larva tastes bad.
  - A 2024 study found that the bitter lucibufagins evolved after firefly light did, so light may not have started out as a warning.
  - The larval lights keep working into the pupa, and for a few days after the adult appears.
- **Bitter Blood** (Adults + larvae carry bitter steroids): Common eastern fireflies carry lucibufagins, bitter steroids in their blood that put predators off. [3][15][16]
  - Lucibufagins were found in large amounts in the blood of adults, and also in larvae.
  - In feeding tests, thrushes rejected two other Photinus species, and lucibufagins were at least partly why.
  - These chemicals block a vital pump in animal cells. Fireflies have evolved a resistant version of the pump, so they are not poisoned by their own defence.
- **Earthworm Hunter** (Earthworms main larval prey): The larva lives on and under the soil and seems to specialise in eating earthworms. [3][1]
  - Firefly larvae have jaws that carry a toxin to overpower soft-bodied prey such as earthworms, snails and slugs.
  - In the lab, scientists raised this species on pieces of earthworm.
  - The larvae live underground and are very hard to find in the wild.
- **Egg Drop** (≈30–50 eggs per female): After mating, a female lays about 30–50 eggs over a few days on moss or in moist soil. [3]
  - Mated females store sperm, then lay their eggs over a few days.
  - In some fireflies even the eggs glow faintly, using a second luciferase gene.
  - The larvae that hatch spend most of their lives in the soil.

### Body parts

- **Head shield** (1 black spot on a pink shield) [1][2]
  - A shield-like plate called the pronotum covers the head from above, so the head is hard to see from on top.
  - In this species the shield is pale yellow with a black spot in the middle, ringed with pink or red.
  - When the firefly is grabbed, bitter fluid is reported to ooze from the edges of the shield and wing covers.
- **Eyes** (2–3 s a female waits, then answers) [3][4][5]
  - Courtship is a conversation by sight: a male flashes, and a female who sees it answers after a delay of 2–3 s.
  - Common eastern fireflies are active at twilight, when there is still some light in the sky.
  - In flashing fireflies like Photinus, females choose their mates based on the males’ flash signals.
- **Antennae** [6]
  - Scientists long thought flashing fireflies don’t use smell to find mates.
  - A 2025 study of this species found smell-receptor genes in the antennae, and some are more active in one sex than the other.
  - That hints that smell may still matter to common eastern fireflies, but what they smell is not yet known.
- **Mouth** (Usually none adult meals) [3][2]
  - Adult common eastern fireflies are usually thought not to feed at all.
  - Even so, both sexes have been seen drinking nectar from common milkweed flowers.
  - Most of the energy for the adult’s 2–3 weeks of flying and flashing is stored up while it is a larva.
- **Wing covers** [1][3][2]
  - Fireflies are not flies: they are beetles, in the family Lampyridae.
  - Like other beetles they have hardened front wings (elytra) that cover the flying wings. In fireflies these covers are soft and somewhat leathery.
  - In this species the covers are black or brown with a pale yellow border.
- **Flight wings** (J shaped flash path) [3][2]
  - The thin flight wings fold away under the wing covers when the beetle lands.
  - Males patrol by flying low above the ground.
  - Each flash is given as the male dips and then climbs, drawing a J of light. That is where the name “big dipper firefly” comes from.
- **Lantern** (2 segments of male lantern) [3][7][8]
  - The light organ, or lantern, is on the underside of the abdomen.
  - In males it fills the underside of abdominal segments 6 and 7. In females it is a smaller spot on segment 6 only.
  - The light is yellow-green. Its exact shade varies between populations, and pigments in the lantern may help tune it.
- **Light cells** (41% of reactions make light) [3][7][9]
  - The lantern is packed with light-making cells called photocytes.
  - Inside them, the enzyme luciferase uses ATP (the cell’s fuel), magnesium and oxygen to change luciferin, and the reaction gives off light.
  - Oxygen is often the limiting ingredient. Tiny air tubes branch into the lantern in a “tracheal brush” to bring it in.
- **Legs** [3]
  - Like every insect, a firefly has six legs.
  - Females perch on grass and other plants during courtship.
  - When a female sees a male’s flash, she twists her abdomen towards it and gives one answering flash.

### Stats

| Stat | Value | Notes |
|---|---|---|
| Length | 9–19 mm | reported range for adults [2][1] |
| Male flash | ≈0.3 s | each patrol flash [3] |
| Between flashes | 5–10 s | a patrolling male repeats his flash [3] |
| Female answer | 2–3 s | delay after the male’s flash [3] |
| Adult life | 2–3 weeks | as a flying, flashing adult [3] |
| Larval life | up to 2 years | reportedly, before it pupates [2] |
| Eggs | ≈30–50 | laid on moss or moist soil [3] |
| Light per reaction | 41% | of reacting luciferin molecules make a photon (2008) [13][9] |
| Firefly species | ≈2,000 | worldwide; 35 described Photinus in North America [19][10] |
| Genome | 448.8 million | DNA letters mapped to chromosomes (95% of the 2018 assembly) [3] |

### Photos

- [Common eastern firefly resting on a plant](https://commons.wikimedia.org/wiki/File:Common_Eastern_firefly_(41298775405).jpg) (photo: Melissa McMasters, CC BY 2.0)
- [In flight, lantern glowing](https://commons.wikimedia.org/wiki/File:F2019-07-02_1982.jpg) (photo: Terry Priest, CC BY-SA 4.0)
- [Rock Creek Park, Washington, DC](https://commons.wikimedia.org/wiki/File:Common_Eastern_Firefly_(27524503504).jpg) (photo: Katja Schulz, CC BY 2.0)
- [Rock Creek Park, Washington, DC](https://commons.wikimedia.org/wiki/File:Common_Eastern_Firefly_(27858834330).jpg) (photo: Katja Schulz, CC BY 2.0)
- [Mount Pleasant, Washington, DC](https://commons.wikimedia.org/wiki/File:Eastern_Firefly_(14430208997).jpg) (photo: Katja Schulz, CC BY 2.0)
- [Photographed in Virginia in June](https://commons.wikimedia.org/wiki/File:Eastern_firefly_(Photinus_pyralis)%2C_June_2025%2C_Virginia.jpg) (photo: Celari817, CC BY 4.0)
- [Common eastern firefly, eastern USA](https://commons.wikimedia.org/wiki/File:Firefly_2013-07-11_121-1.jpg) (photo: Terry Priest, CC BY-SA 3.0)
- [A Photuris firefly, Lower Suwannee National Wildlife Refuge, Florida](https://commons.wikimedia.org/wiki/File:Flickr_-_ggallice_-_Lightning_bug.jpg) (photo: Geoff Gallice, CC BY 2.0)
- [A Photuris firefly, Great Smoky Mountains National Park](https://commons.wikimedia.org/wiki/File:Lampyridae-_Photuris_sp._-_50024627032.jpg) (photo: Kristof Zyskowski & Yulia Bereshpolova, CC BY 2.0)

### Questions

- **Are fireflies dangerous?** No. Common eastern fireflies have no sting, and adults usually don’t even eat. Their defence is bitter-tasting chemicals in their blood. Watch them rather than catch them, and never put one in your mouth. [3][15]
- **Why do fireflies light up?** Mostly to find a mate. Males flash a species-specific code and females answer, so each can recognise their own species. Larvae glow too, probably to warn predators that they taste bad. [3][4][10]
- **How do fireflies make light?** Light cells in the lantern use the enzyme luciferase, with ATP, magnesium and oxygen, to change a molecule called luciferin. About 41% of the reacting molecules give off light, according to a 2008 measurement. [3][13][9]
- **What do fireflies eat?** Common eastern firefly larvae live in the soil and mainly eat earthworms. Adults usually don’t eat, though some have been seen drinking milkweed nectar. [3]
- **How long do fireflies live?** Adults live only about 2–3 weeks. Most of the life cycle is spent as a larva in the soil, which may take up to 2 years. [3][2]
- **Are fireflies disappearing?** Some are. Of 132 North American fireflies assessed for the IUCN Red List, at least 18 are threatened. The common eastern firefly is listed as Least Concern. Habitat loss, light pollution and pesticides are the main threats. [26][25][19]
- **How can I help fireflies in my garden?** Switch off or dim outdoor lights at night, since bright lights cut firefly courtship and mating. Avoid pesticides, and use a red light if you go out to watch them. [5][27][19][24]
- **Are glowworms and fireflies the same?** Firefly larvae are often called glowworms, and they do glow. The common eastern firefly larva has two small lights near its tail end. [1][7]

### Firefly myths and facts

Tap Myth or Fact for each claim, then check the answer.

- "Fireflies are a kind of fly." **Myth!** Fireflies are beetles, in the family Lampyridae. Like other beetles they have front wings that cover the flying wings. [1][3]
- "Firefly light is almost 100% efficient." **Myth!** That idea came from a 1959 measurement of 88%. A 2008 re-measurement found that about 41% of reacting luciferin molecules give off light. That is still very high for a chemical glow. [13][9]
- "Baby fireflies glow too." **Fact!** Larvae glow from two small spots near the tail end. Their glow rises and falls slowly instead of flashing. [7]
- "Some fireflies eat other fireflies." **Fact!** Female Photuris fireflies copy the answer flashes of Photinus females, then catch and eat the males that fly in. [17][18]
- "Adult fireflies need to eat a lot." **Myth!** Adult common eastern fireflies are usually thought not to feed, though some have been seen sipping milkweed nectar. They live on energy stored as larvae. [3]
- "All fireflies flash in sync." **Myth!** Only some species flash together, such as the synchronous firefly of the Great Smoky Mountains. Common eastern firefly males each flash on their own rhythm. [20][3]
- "Birds find fireflies tasty." **Myth!** In feeding tests thrushes rejected two Photinus species, partly because of bitter steroids called lucibufagins. Common eastern fireflies carry them too. [15][3]
- "Bright garden lights can stop fireflies finding mates." **Fact!** In field experiments, added night lighting reduced courtship and mating success in common eastern fireflies. [5]

### How common eastern fireflies talk with light

A firefly courtship is a quick conversation in light. Each species has its own code of flash length, gap and shape.

- **≈0.3 s** Male flash. A patrolling male gives one short flash, about 0.3 s long. [3]
- **5–10 s** Gap. He repeats it every 5–10 s while flying low over the grass. [3]
- **J** Shape. He flashes while dipping and climbing, so the light draws a J. [3][2]
- **2–3 s** Female’s delay. A female answers with one flash after 2–3 s. The delay tells the male she is his species. [3]
- **35** Photinus codes. North America has 35 described Photinus species, each with simple on-off signals of its own. [10]
- **82%** Sync helps. In the synchronous firefly, females answered 82% of in-step flashes but as few as 3% of out-of-step ones. [20]

Photuris “femme fatale” females can fake the female answer of Photinus fireflies, so answering is not always safe for the males.

### Firefly records

Superlatives and record holders, each checked against its source.

- More light per reaction than lab glow: Firefly light reaction, 41% vs 1.2% (light per reaction, about 34 times luminol’s) [9][13]
- A glowing plant from a firefly gene: Common eastern firefly luciferase, 1986 (tobacco plants carrying its gene made light when given luciferin) [21]
- Genome pioneer: Common eastern firefly, 2018 (genome sequenced, with a Japanese firefly and a glowing click beetle) [3]
- Ancient family: Fireflies, 100+ million years (since the two main firefly lineages split) [3]
- Split-second teamwork: Synchronous firefly (Photinus carolinus), Milliseconds (males flash in step to within thousandths of a second) [20]
- Firefly fans: Firefly tourism, 1 million+ a year (visitors to firefly sites in at least 12 countries) [22]

### A common eastern firefly’s life

Most of a firefly’s life is spent underground. The flashing adult lasts only a few weeks.

- **Early summer**: Eggs in the soil. A mated female lays about 30–50 eggs over a few days, on moss or in moist soil. [3]
- **Hatching**: A glowing larva. The wingless larva has two small lights near its tail end that glow softly. [7]
- **Up to 2 years**: Underground hunter. The larva lives on and under the soil and eats mostly earthworms. It may take up to 2 years before it pupates. [3][2]
- **Pupa**: Two sets of lights. In the pupa the larval lights still glow, and later the new adult lantern starts working alongside them. [7]
- **Spring–summer**: Adult appears. Adults come out in spring and summer and are easiest to see around twilight. [1][2]
- **Dusk**: Flash and answer. Males patrol with J-shaped flashes; females answer from the grass after 2–3 s. [3]
- **2–3 weeks**: Lights out. Adults live only about 2–3 weeks, mostly on energy stored as larvae. [3]

### Common eastern firefly vs synchronous firefly vs Photuris

Three North American fireflies, three very different ways of using light.

| | Common eastern firefly | Synchronous firefly | Photuris fireflies |
|---|---|---|---|
| Scientific name [23][20][17] | Photinus pyralis | Photinus carolinus | Photuris (a genus of many species) |
| Famous for [3][20][17] | The J-shaped “big dipper” flash | Males flashing in step together | The femme fatale trick |
| Male flashing [3][20] | ≈0.3 s flash every 5–10 s, on his own rhythm | In sync with other males, to within milliseconds | Varies by species |
| Most active [5][24] | Twilight | Night displays in late May–June (Great Smoky Mountains) | After dark (e.g. Photuris versicolor) |
| Adult females eat other fireflies? [18][17] | No: it is prey | No: it is prey | Yes: they hunt Photinus males |
| Bitter lucibufagins [3][18][16] | Makes its own | Photinus fireflies make their own | Can’t make them; steals them from prey |
| IUCN Red List [25] | Least Concern | Least Concern | Varies: Bethany Beach firefly is Critically Endangered |

Synchronous firefly flashing is famous in Great Smoky Mountains National Park, where the park runs a lottery for viewing nights to protect the fireflies.

### Are common eastern fireflies endangered?

No: this firefly is listed as Least Concern and is still common in lawns and fields. But some North American fireflies are in real trouble, and light pollution affects even common ones.

- **IUCN Red List:** Least Concern (LC). Widespread east of the Rocky Mountains, in fields, meadows, suburban lawns, woodland edges and even cities. [25][23][26][3][2]
- IUCN Red List, March 2021
- **Threat: Light pollution** (Fewer matings): Bright lights at night drown out flashes. In experiments, added lighting reduced courtship and mating success in this species and cut flashing in a night-active firefly by about 70%. [5][27][28]
- **Threat: Habitat loss** (Top 3): Experts surveyed worldwide named habitat loss, light pollution and pesticide use as the most serious threats to fireflies. [19][29]
- **Threat: Pesticides**: Pesticide overuse is one of the main threats linked to recent firefly declines. [19][29]
- **Threat: Climate change** (Drought, sea rise): Drought and rising seas threaten some North American firefly habitats. [26][29]
- **Helping: Lights off**: Turning off, dimming or adjusting outdoor lights reduces their effect on fireflies and other night insects. [27][5]
- **Helping: Red light only**: When watching fireflies, cover your torch with red film, use it only while walking, point it at the ground and switch it off when you arrive. [24]
- **Helping: Watch, don’t collect**: Parks limit visitor numbers to protect firefly displays. Enjoy them where they are. [24][22]
- **Helping: Red List checks** (132 species): Scientists have assessed 132 North American fireflies. At least 18 (14%) are threatened, and nearly half lack enough data. [26][30]
- **Bethany Beach firefly (Photuris bethaniensis)** (CR): Critically Endangered. [25]
- **Southwest spring firefly (Bicellonycha wickershamorum)** (VU): Vulnerable. [25]
- **Synchronous firefly (Photinus carolinus)** (LC): Least Concern, but its famous displays draw so many people that viewing is managed by lottery. [25][24]

### Firefly light signals

- One short flash on a rising J: A male searching for a female of his own species. [3]
- A single flash from the grass, 2–3 s later: A female answering a male she has seen. [3]
- Female twists her abdomen towards a flash: Aiming her answer at the male. [3]
- Slow, steady glow from a larva: Probably a warning that it tastes bad. [7][3]
- Bitter droplets when grabbed: Reportedly a defence, oozing from the shield and wing covers. [2]
- Fewer flashes under bright lights: Artificial light disrupts courtship and cuts mating success. [5]

### Sexes & stages

- **Male**: Big lantern: the whole underside of abdominal segments 6 and 7 lights up. Flies low at dusk, flashing on a rising J. (The searcher: flashes about every 5–10 s) [3]
- **Female**: Smaller lantern: a single spot on segment 6 only. Perches on grass and other plants instead of patrolling. (The answerer: replies 2–3 s after a male’s flash) [3][7]
- **Larva**: Flattened, segmented and wingless, covered in plates, with two small glowing spots on abdominal segment 8. (Hunts earthworms in the soil; reportedly may take up to 2 years before it turns into a pupa) [7][1][3][2]
- **Photuris firefly (look-alike)**: A different firefly genus, the “femme fatale” fireflies. Females copy the answer flashes of Photinus females to lure the males in. (Hunts Photinus males and steals their bitter defence chemicals) [17][18]

### Firefly quiz

1. What kind of insect is a firefly? **A beetle.** Fireflies are beetles, in the family Lampyridae. [1]
2. What shape does a male common eastern firefly’s flash path make? **A J.** He dips and then climbs while flashing, drawing a J. That is why it is called the big dipper firefly. [3]
3. About how long does a male’s flash last? **0.3 s.** Each patrol flash lasts about 0.3 s and is repeated every 5–10 s. [3]
4. How long does a female wait before she answers? **2–3 s.** She answers with one flash after a 2–3 s delay. [3]
5. Where is the male’s lantern? **Under abdominal segments 6 and 7.** The male’s lantern fills the underside of segments 6 and 7. The female’s is a smaller spot on segment 6. [3][7]
6. What do common eastern firefly larvae mostly eat? **Earthworms.** The larvae live in the soil and seem to specialise in earthworms. [3]
7. How long does an adult common eastern firefly live? **2–3 weeks.** Adults live only about 2–3 weeks. [3]
8. Which fireflies are called “femmes fatales”? **Photuris.** Female Photuris fireflies fake Photinus female answers, then eat the males. [17]
9. What do Photuris females get from eating Photinus males, apart from food? **Bitter defence chemicals.** They gain lucibufagins, which they can’t make themselves and which put off spiders. [18]
10. A 2008 measurement found what share of firefly light reactions give off light? **About 41%.** About 41%. The older figure of 88% came from 1959. [13][9]
11. Which firefly is famous for flashing in sync? **Photinus carolinus.** Males of the synchronous firefly, Photinus carolinus, flash in step to within milliseconds. [20]
12. What colour light do park rangers ask firefly watchers to use? **Red.** Use a red torch, or cover yours with red film, only while walking, and point it at the ground. [24]

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21. [Ow DW, de Wet JR, Helinski DR, Howell SH, Wood KV, DeLuca M (1986). Transient and stable expression of the firefly luciferase gene in plant cells and transgenic plants. Science 234:856–859.](https://doi.org/10.1126/science.234.4778.856)
22. [Lewis SM, Thancharoen A, Wong CH, et al. (2021). Firefly tourism: advancing a global phenomenon toward a brighter future. Conservation Science and Practice 3:e391.](https://doi.org/10.1111/csp2.391)
23. [Wikidata (2026). Photinus pyralis (Q137821).](https://www.wikidata.org/wiki/Q137821)
24. [U.S. National Park Service (2026). Synchronous fireflies. Great Smoky Mountains National Park.](https://www.nps.gov/grsm/learn/nature/fireflies.htm)
25. [GBIF (2026). Photinus pyralis (Linnaeus, 1767): IUCN Red List category (IUCN taxon 164046430).](https://www.gbif.org/species/1162763)
26. [Fallon CE, Walker AC, Lewis S, et al. (2021). Evaluating firefly extinction risk: initial red list assessments for North America. PLoS ONE 16:e0259379.](https://doi.org/10.1371/journal.pone.0259379)
27. [Owens ACS, Cochard P, Durrant J, Farnworth B, Perkin EK, Seymoure B (2020). Light pollution is a driver of insect declines. Biological Conservation 241:108259.](https://doi.org/10.1016/j.biocon.2019.108259)
28. [Owens ACS, Lewis SM (2018). The impact of artificial light at night on nocturnal insects: a review and synthesis. Ecology and Evolution 8:11337–11358.](https://doi.org/10.1002/ece3.4557)
29. [Lewis SM, Jusoh WFA, Walker AC, Fallon CE, Joyce R, Yiu V (2024). Illuminating firefly diversity: trends, threats and conservation strategies. Insects 15:71.](https://doi.org/10.3390/insects15010071)
30. [Xerces Society (2026). Firefly conservation.](https://xerces.org/endangered-species/fireflies)

## Measurements & details

- **Wingspan:** 14-30 mm
- **Size:** 9-19 mm
- **Lifespan:** 14-21 days
- **Leg Count:** 6

## Diet & Feeding

Firefly larvae are hunters that eat mostly earthworms. Adults usually don't feed, though some have been seen sipping nectar.

- **Age differences:** Larvae are predators and eat mostly earthworms. Adults usually don't feed and live on energy stored as larvae.
- **Primary Foods:** Earthworms
- **Foraging Method:** Ambush

## Ecological connections

- **Eaten by:** Photuris fireflies (*Photuris*) — Female Photuris fireflies copy the answer flashes of Photinus females, then catch and eat the males that fly in.
- **Hunts:** Earthworms (*Lumbricidae*) — Firefly larvae live in and under the soil and seem to specialise in eating earthworms.

## Traits

- [Wildlife](https://www.snappit.app/explore/traits/wildlife): Wildlife encompasses all undomesticated animal and plant life existing in their natural habitats.
- [Glowing](https://www.snappit.app/explore/traits/glowing): Pertaining to organisms that emit light through bioluminescence or fluorescence.
- [Nocturnal](https://www.snappit.app/explore/traits/nocturnal): Nocturnal animals are primarily active during the nighttime hours, typically resting or sleeping during the day.

## Collections

- [Insects](https://www.snappit.app/explore/collections/insects)
- [Insects](https://www.snappit.app/explore/collections/insects-and-bugs)

## Safety

**Danger:** 0/5 · No known danger

Fireflies are harmless: they don't sting or bite. Watch them where they are instead of catching them, and keep lights low so they can find each other.

## Frequently Asked Questions

### How to identify Firefly?

Look for hard wing covers meeting in a line down the back, then compare the antennae, body shape, legs and markings. Metallic colors shift a lot with lighting. Beetle Identifier: upload a photo and compare the visible details.

### What is Firefly's wingspan?

14-30 mm

### How big is Firefly?

9-19 mm

### How long does Firefly live?

14-21 days

### What does Firefly eat?

Firefly larvae are hunters that eat mostly earthworms. Adults usually don't feed, though some have been seen sipping nectar.

### Where is Firefly usually found?

Fields, meadows, lawns and woodland edges, even in towns and cities.

### How many legs does Firefly have?

6

## Where to spot

- [Alabama City Wall Street Historic District](https://www.snappit.app/guides/places/alabama-city-wall-street-historic-district) — Alabama, US · Historic District
- [American Baptist College](https://www.snappit.app/guides/places/american-baptist-college) — Tennessee, US · Campus
- [Anderson University](https://www.snappit.app/guides/places/anderson-university) — South Carolina, US · Campus
- [Bishop Hill Colony](https://www.snappit.app/guides/places/bishop-hill-colony) — Illinois, US · Historic District
- [Bloomingdale](https://www.snappit.app/guides/places/bloomingdale) — District of Columbia, US · Neighborhood
- [Boerner Botanical Gardens](https://www.snappit.app/guides/places/boerner-botanical-gardens) — Wisconsin, US · Botanical Garden

[View all places to see Firefly](https://www.snappit.app/guides/where-to-see/firefly)

## More Insects

- [Common Eastern Bumble Bee](https://www.snappit.app/explore/common-eastern-bumble-bee) (*Bombus impatiens*)
- [Spotted Lanternfly](https://www.snappit.app/explore/spotted-lanternfly) (*Lycorma delicatula*)
- [Brown-belted Bumble Bee](https://www.snappit.app/explore/brown-belted-bumble-bee) (*Bombus griseocollis*)
- [Eastern Carpenter Bee](https://www.snappit.app/explore/eastern-carpenter-bee) (*Xylocopa virginica*)

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Source: [Firefly: Characteristics, Facts & Places to See — Snappit](https://www.snappit.app/explore/firefly)