---
title: "What the sources say about the Common Eastern Firefly | AnimalTracks.wiki"
description: "50 claims from the Common Eastern Firefly profile, each beside the words of the source that backs it."
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---

# What the sources say about the Common Eastern Firefly (*Photinus pyralis*)

> 50 claims from the Common Eastern Firefly profile, each beside the words of the source that backs it. A "..." marks a cut in a quote and [brackets] an insertion.

Profile: [Common Eastern Firefly](https://animaltracks.wiki/animals/common-eastern-firefly/)

## Walker (2021). Photinus pyralis. The IUCN Red List of Threatened Species 2021: e.T164046430A166771623.

https://doi.org/10.2305/iucn.uk.2021-1.rlts.t164046430a166771623.en

| The page says | The source says |
| :--- | :--- |
| Least Concern | IUCN Red List category: Least Concern (LC). (note: stats.conservationStatus; GBIF copy of the Red List, taxon id checked in the DOI) |
| No. The IUCN Red List rates the species Least Concern. | IUCN Red List category: Least Concern (LC). |

## Fallon et al. (2018). Firefly genomes illuminate parallel origins of bioluminescence in beetles. eLife.

https://doi.org/10.7554/elife.36495

| The page says | The source says |
| :--- | :--- |
| takes flight and gives one flash of about 300 milliseconds roughly every 5 to 10 seconds | Males initiate courtship by flying low above the ground while repeating a single ~300 ms patrol flash at ~5–10 s intervals (note: field: habitat generalist claim, fields listed) |
| As he dips down and then rises, his light traces a J shape | Males emit their patrol flash while dipping down and then ascending vertically, creating a distinctive J-shaped flash gesture |
| A female of his species perches on a plant and answers with a single flash after a delay of 2 to 3 seconds | females perch on vegetation and respond to a male patrol flash by twisting their abdomen toward the source of the flash and giving a single response flash given after a 2–3 s delay |
| Male Common Eastern Fireflies carry lucibufagins in their hemolymph, the insect version of blood | Anti-predator chemical defenses of male P. pyralis include several bufadienolides, known as lucibufagins, that circulate in the hemolymph (note: 'the insect version of blood' is a gloss of hemolymph; Cornell 1997 calls it 'firefly blood') |
| When a male is attacked, he releases copious amounts of hemolymph that coagulates rapidly | When attacked, P. pyralis males release copious amounts of rapidly coagulating hemolymph |
| This reflex bleeding may also give him physical protection against small predators | such ‘reflex-bleeding’ may also provide physical protection against small predators |
| The first luciferase gene was cloned from this species | the first luciferase gene was cloned from this species |
| luciferase is now widely used as a reporter in biomedical research | led to the widespread use of luciferase as a reporter with unique applications in biomedical research and industry |
| Adults live 2 to 3 weeks | Adult P. pyralis live 2–3 weeks |
| they are typically considered non-feeding, though both sexes have been reported drinking milkweed nectar | although these adults are typically considered non-feeding, both sexes have been reported drinking nectar from the flowers of the milkweed Asclepias syriaca |
| Mated females lay roughly 30 to 50 eggs on moss or moist soil | Mated females store sperm and lay ~30–50 eggs over the course of a few days on moss or in moist soil. |
| the eggs take 2 to 3 weeks to hatch | The eggs take 2–3 weeks to hatch. |
| They live on and beneath the soil and appear to specialize in earthworms | P. pyralis larvae are predatory, live on and beneath the soil, and appear to be earthworm specialists |
| In the northern parts of the range, slower development likely requires them to overwinter at least twice | In the northern parts of its range, slower development likely requires P. pyralis to overwinter at least twice, most likely as larvae. |
| The species is a habitat generalist | A habitat generalist, P. pyralis occurs in fields, meadows, suburban lawns, forests, and woodland edges, and even urban environments. |
| It turns up in fields, meadows, suburban lawns, forests and woodland edges, and even in cities such as New York and Washington D.C | P. pyralis occurs in fields, meadows, suburban lawns, forests, and woodland edges, and even urban environments. For example, the authors have observed P. pyralis flashing in urban New York City and Washington D.C. |
| It is found with confidence from roughly Connecticut to Texas | P. pyralis is found with confidence roughly from Connecticut to Texas |
| whose males trace a J of light at dusk | Males emit their patrol flash while dipping down and then ascending vertically, creating a distinctive J-shaped flash gesture (note: tagline; dusk from the same source: "At dusk males take flight") |
| bleed defensive steroids when attacked | When attacked, P. pyralis males release copious amounts of rapidly coagulating hemolymph (note: tagline; steroids = lucibufagins circulating in the hemolymph, claimed in the body) |
| Fields, meadows, lawns and woodland edges, roughly from Connecticut to Texas | P. pyralis occurs in fields, meadows, suburban lawns, forests, and woodland edges, and even urban environments. (note: stats.habitat; range in the next claim) |
| roughly from Connecticut to Texas | P. pyralis is found with confidence roughly from Connecticut to Texas (note: stats.habitat) |
| Larvae appear to specialize in earthworms | P. pyralis larvae are predatory, live on and beneath the soil, and appear to be earthworm specialists (note: stats.diet) |
| adults are typically considered non-feeding | although these adults are typically considered non-feeding (note: stats.diet) |
| bleed defensive steroids | When attacked, P. pyralis males release copious amounts of rapidly coagulating hemolymph (note: stats.superpower; the steroids circulate in the hemolymph per the lucibufagin claim) |
| Only two to three weeks as an adult. | Adult P. pyralis live 2–3 weeks |
| Before that it is a hunting larva on and beneath the soil | P. pyralis larvae are predatory, live on and beneath the soil |
| in the north slow growth likely means at least two winters, most likely spent as a larva | In the northern parts of its range, slower development likely requires P. pyralis to overwinter at least twice, most likely as larvae. (note: 'in the north' for 'In the northern parts of its range'; 'slow growth' for 'slower development') |
| The larvae are the predators | P. pyralis larvae are predatory (note: adults are typically considered non-feeding, per the claim above) |
| A female Common Eastern Firefly answers a male's flash after a delay of 2 to 3 seconds | females perch on vegetation and respond to a male patrol flash by twisting their abdomen toward the source of the flash and giving a single response flash given after a 2–3 s delay (note: vibe.reason; same quote as the body claim "A female of his species perches on a plant and answers with ") |
| tags: chemical-defense | Anti-predator chemical defenses of male P. pyralis include several bufadienolides, known as lucibufagins, that circulate in the hemolymph (note: task #1009; the next sentence of the same paragraph: 'When attacked, P. pyralis males release copious amounts of rapidly coagulating hemolymph'. Same reading as the seven-spot ladybird's reflex bleeding (#998)) |

## Eisner et al. (1997). Firefly “femmes fatales” acquire defensive steroids (lucibufagins) from their firefly prey. Proceedings of the National Academy of Sciences.

https://doi.org/10.1073/pnas.94.18.9723

| The page says | The source says |
| :--- | :--- |
| Females of the genus Photuris prey on males of the genus Photinus, which includes this species, by imitating the reply of a Photinus female | Female fireflies of the genus Photuris, the so-called firefly "femmes fatales," prey on male fireflies of the genus Photinus. The females are able to entrap the males by faking the flash signal characteristics of the Photinus female. (note: the species is Photinus pyralis, the genus is in its binomial) |
| Her meal gives her more than food | We found that by feeding on Photinus males, Photuris females gain more than nutrients. |
| Female Photuris are unable to make lucibufagins, the defensive steroids that Photinus males carry | They also acquire defensive steroidal pyrones called lucibufagins, which are contained in Photinus but which Photuris fireflies are unable to produce on their own. (note: the next sentence has its own claim) |
| Phidippus jumping spiders reject a Photuris female that has eaten a male or been fed the chemical | Photuris females that eat Photinus males or lucibufagin are rejected by Phidippus jumping spiders. |
| They acquire them by eating the males | by feeding on Photinus males, Photuris females gain more than nutrients. They also acquire defensive steroidal pyrones called lucibufagins |
| Other fireflies fake replies like this | The females are able to entrap the males by faking the flash signal characteristics of the Photinus female. (note: genus scope: the source names Photinus females, not P. pyralis) |

## Segelken (1997). Lured and liquidated, gullible male fireflies supply 'femmes fatales' with a lifesaving chemical. Cornell Chronicle.

https://www.news.cornell.edu/chronicle/97/9.4.97/firefly.html

| The page says | The source says |
| :--- | :--- |
| That gap is the password | The password from the female of the appropriate species is encoded in the time-delay between the male's flash pattern and her single flash response |
| A male who flies down to meet her can become her meal | the femmes fatales fireflies are luring males close enough to eat them |
| Lucibufagins closely resemble the bufalin steroids in the venom of poisonous Chinese toads, so Cornell researchers built the name from the Latin words for "light" and "toad" | Because the fireflies' defensive compound was found to have a close chemical resemblance to bufalin steroids in the venom of poisonous Chinese toads, the Cornell researchers combined the Latin terms for "light" and "toad," respectively, and coined the word, "lucibufagin." |
| Males flash a timed courtship code | The password from the female of the appropriate species is encoded in the time-delay between the male's flash pattern and her single flash response (note: stats.superpower) |
| No. Entomologists regard fireflies as beetles, not true flies. | which entomologists regard as beetles, not true flies |
| that gap is the password | The password from the female of the appropriate species is encoded in the time-delay between the male's flash pattern and her single flash response (note: vibe.reason; same quote as the body claim "That gap is the password") |

## McKenzie. Photinus pyralis. Animal Diversity Web, University of Michigan.

https://animaldiversity.org/accounts/Photinus_pyralis/

| The page says | The source says |
| :--- | :--- |
| At dusk, a male Common Eastern Firefly takes flight | At dusk males take flight while females wait perched on the ground or in bushes. |
| The light comes from the last segment of the abdomen, which flashes yellow-green | The last segment of the abdomen is the section that lights up, flashing bright yellow-green. |
| It runs on a reaction in which the enzyme luciferase oxidizes a molecule called luciferin, using ATP, the energy molecule cells run on, plus magnesium and oxygen | The firefly produces light in the presence of oxygen, magnesium, and adenosine triphosphate by using an enzyme, luciferase, to oxidize a complex organic compound, luciferin. (note: 'the energy molecule cells run on' is a gloss of ATP) |
| this insect is a beetle | The common eastern firefly is, in fact, not a fly, but a type of beetle. |
| 10 to 14 mm long | Range length 10 to 14 mm |
| A beetle | The common eastern firefly is, in fact, not a fly, but a type of beetle. (note: tagline) |