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What the sources say

Bombardier BeetleBrachinus crepitans

Every figure, record and mechanism on the Bombardier Beetle profile was written from a source, and this is the working table behind it: 46 claims checked word for word against these sources. The left column is what the page says. The right column is the source's own words, copied, not paraphrased; a ... marks a cut and[brackets] an insertion. Open any source and check it yourself.

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Source
01

Vogel et al. 2025

Vogel et al. (2025). Molecular basis of the explosive defence response in the bombardier beetle Brachinus crepitans. Royal Society Open Science.

The page saysBrachinus crepitans has been recorded in Germany, where researchers studying its chemistry collected live specimens from Nordrhein-Westfalen
The source saysAdult bombardier beetles (B. crepitans) were collected from Nordrhein-Westfalen, Germany, with permission from the Nature Conservation Agency in Koblenz
The page saysA pair of glands sits in its abdomen
The source sayswhich forcibly expel a hot spray of noxious p-benzoquinones from their paired abdominal defensive glands when attacked by vertebrate or invertebrate predators
The page sayseach with a reservoir holding a solution of roughly 25 percent hydrogen peroxide and 10 percent hydroquinones, carried in an oily, non-reactive solvent
The source saysan aqueous solution of approximately 25% hydrogen peroxide and approximately 10% p-hydroquinones along with approximately 10% n-alkanes as a non-reactive second liquid phase acting as a solventNote: 'oily' glosses n-alkanes for the audience; the paper's 'approximately' is kept as 'roughly'.
The page saysMuscles around the reservoir squeeze that mixture through a one-way valve into a second, armor-walled chamber that researchers think is lined with cells producing catalase and peroxidase enzymes
The source saysthese muscles contract to force the stored chemicals ... through a one-way valve into the rigid-walled, sclerotized RXC lined with cells that are thought to secrete catalases and peroxidasesNote: The 2025 paper hedges the enzyme lining ('although this has not been confirmed'), so the page hedges it too, even though the older UTEP page states it flatly.
The page saysMixing the two sets off an explosive reaction that turns the hydroquinones into benzoquinones, releasing oxygen, water and 48.5 kilocalories of heat per mole of benzoquinone made
The source saysMixing initiates an explosive exothermic reaction that produces p-benzoquinones, free oxygen and water, also generating 48.5 kcal of thermal energy per mol p-benzoquinones
The page saysThe spray leaves the beetle at up to 100°C, moving as fast as 10 meters a second, and it can land up to 30 centimeters away
The source saysat temperatures of up to 100°C, at speeds of up to 10 m s−1 and over distances of up to 30 cm
The page saysThe pressure cannot push back through the one-way valve, and the discharge leaves as what researchers call a pulsed jet
The source saysThe high overpressure in the RXC results in an explosive secretory discharge that cannot pass back through the valve into the RC [10]. It is therefore ejected as a noxious pulsed jet
The page saysa rapid series of bursts aimed at the point where something is touching the beetle
The source saysThe defence secretion is ejected as a jet of fine mist without visible dissipation ... in a rapid series of consecutive pulses. ... Higher magnification highlights the precision with which the beetle orientates the jet towards the contact point with forcepsNote: Figure 1 caption, and it is B. crepitans: this is the species-level support for 'rapid pulses', which the 500-per-second figure (another species) is not.
The page sayswarming collected secretions to 90°C for ten minutes barely slowed the catalase enzymes down
The source sayswe mixed the defensive secretions collected from 30 beetles with 30% hydrogen peroxidase at different temperatures for different durations, and used bubble formation to quantify enzyme activity. Even exposure to 90°C for 10 min did not significantly inhibit the formation of bubbles, confirming the outstanding thermal resistance of the catalasesNote: The experiment tested the enzymes, not the chamber lining, so the sentence credits the chemistry.
The page saysEmptied by repeated firing, the glands need about 13 hours to refill completely, and the spray then returns to normal
The source saysThe glands still produced defensive secretions after 3 h (four rounds of stimulation), but they were depleted after 6 h (seven rounds of stimulation). After a rest period, the spray count and duration in response to stimulation returned to normal, indicating complete replenishment of the MGS after 13 hNote: The 13 h is the refill after repeated stimulation emptied the glands, not the recovery from a single discharge.
The page saysExplosive Chemical Spray Up To 100°C
The source saysejected as a noxious pulsed jet ... at temperatures of up to 100°CNote: stats.superpower; 'Up To' restored: the label previously read a flat '100°C', which is stronger than the source.
The page saysFired in Rapid Pulses
The source saysThe defence secretion is ejected as a jet of fine mist without visible dissipation ... in a rapid series of consecutive pulsesNote: stats.superpower; figure 1 caption, B. crepitans, so 'rapid pulses' is species-level and does not lean on the Stenaptinus figure.
The page saysblasts attackers with a chemical spray up to 100°C
The source saysIt is therefore ejected as a noxious pulsed jet ... in the direction of the perceived threat ... at temperatures of up to 100°CNote: tagline; 'up to' restored, matching the source.
The page saysfired in rapid pulses
The source saysThe defence secretion is ejected as a jet of fine mist without visible dissipation ... in a rapid series of consecutive pulsesNote: tagline; B. crepitans figure 1 caption.
The page saysChemical pressure builds in a sealed reaction chamber until it fires in rapid, explosive pulses
The source saysMixing initiates an explosive exothermic reaction ... The high overpressure in the RXC results in an explosive secretory discharge that cannot pass back through the valve into the RC ... It is therefore ejected as a noxious pulsed jetNote: vibe.reason; 'sealed' is the rigid-walled chamber whose discharge cannot pass back through the valve, and 'until it fires' is the paper's own sequence: overpressure builds in the chamber and therefore the discharge is ejected. 'rapid pulses' is figure 1's 'a rapid series of consecutive pulses' for B. crepitans.
The page saysIt mixes two stored chemicals when it needs to.
The source saysGlandular secretions enter the CD and accumulate in the RC ... When the beetle is provoked, these muscles contract to force the stored chemicals ... through a one-way valve into the rigid-walled, sclerotized RXCNote: FAQ 1 framing sentence: the two chemicals are stored in the reservoir and combine in the reaction chamber only when the beetle is provoked.
The page saysThe beetle keeps hydrogen peroxide and hydroquinones in a reservoir chamber, then squeezes them through a one-way valve into a second chamber that is thought to be lined with catalase and peroxidase enzymes.
The source saysthese muscles contract to force the stored chemicals—an aqueous solution of approximately 25% hydrogen peroxide and approximately 10% p-hydroquinones ... through a one-way valve into the rigid-walled, sclerotized RXC lined with cells that are thought to secrete catalases and peroxidasesNote: FAQ 1; the source's 'thought to' is kept verbatim, because the 2025 paper says the enzyme lining 'has not been confirmed'.
The page saysThe mixing sets off an explosive reaction that produces benzoquinones, oxygen and water, and the mixture leaves the beetle's abdomen at up to 100°C.
The source saysMixing initiates an explosive exothermic reaction that produces p-benzoquinones, free oxygen and water ... It is therefore ejected as a noxious pulsed jet ... at temperatures of up to 100°C
The page saysThe chamber walls are rigid and hardened, and a one-way valve stops the blast pushing back into the reservoir.
The source saysthrough a one-way valve into the rigid-walled, sclerotized RXC ... The high overpressure in the RXC results in an explosive secretory discharge that cannot pass back through the valve into the RCNote: FAQ 2, rewritten: the old answer's premise (releasing the pressure at once) was not in any source, and its ref did not state the mechanism it claimed.
The page saysBoth chambers are lined on the inside with cuticle, the tough material an insect's shell is made of, which protects the cells underneath from the chemicals and the heat.
The source saysThe luminal surfaces of the chambers are lined with cuticular material to protect the underlying cells from the chemicals and heatNote: FAQ 2; 'the tough material an insect's shell is made of' defines cuticle for the audience.
The page saysEven the enzymes cope: secretions collected from Brachinus crepitans and held at 90°C for ten minutes still worked.
The source saysTo evaluate the thermal resistance of the catalase from B. crepitans, we mixed the defensive secretions collected from 30 beetles with 30% hydrogen peroxidase at different temperatures for different durations, and used bubble formation to quantify enzyme activity. Even exposure to 90°C for 10 min did not significantly inhibit the formation of bubbles
The page saysNot Evaluated
The source saysthe bombardier beetle Brachinus crepitansNote: stats.conservationStatus. No reference in the profile states a Red List status; this quote anchors the species name only. GBIF's copy of the Red List returns NOT_EVALUATED for Brachinus crepitans (Linnaeus, 1758), usage key 4474861 (https://api.gbif.org/v1/species/4474861/iucnRedListCategory), checked 2026-09-17, and source:prefetch found no Crossref assessment DOI (2026-09-15). The house convention for an unassessed species is to carry no status reference (#596).

Source
02

Dean et al. 1990

Dean et al. (1990). Defensive Spray of the Bombardier Beetle: a Biological Pulse Jet. Science.

The page saysA different bombardier beetle, Stenaptinus insignis, was recorded spraying in pulses about 500 times a second, a firing pattern researchers compared to the pulse-jet engine of a World War Two flying bomb
The source saysThe defensive spray of the bombardier beetle Stenaptinus insignis is ejected in quick pulses (at about 500 pulses per second) rather than as a continuous stream. ... The ejection system of the beetle shows basic similarity to the pulse jet propulsion mechanism of the German V-1 "buzz" bomb of World War II.Note: Different species from B. crepitans; the body names Stenaptinus insignis explicitly rather than generalizing the pulse rate to the profile's species.

Source
03

Sugiura & Sato 2018

Sugiura & Sato (2018). Successful escape of bombardier beetles from predator digestive systems. Biology Letters.

The page saysIn one bombardier beetle at least, the weapon works from inside a predator
The source saysOur experiment showed that P jessoensis ejected hot chemicals inside the toads, thereby forcing the toads to vomit.Note: Scoped to the studied species: the result is Pheropsophus jessoensis, not B. crepitans, and the next sentence names it.
The page saysIn a laboratory study of a related species, Pheropsophus jessoensis, toads (Bufo japonicus and B. torrenticola) swallowed the beetles, and 43 percent of the toads vomited them back up between 12 and 107 minutes later, every one still alive and active
The source sayswe investigated how the bombardier beetle Pheropsophus jessoensis escapes from two toad species, Bufo japonicus and B torrenticola, under laboratory conditions. ... Although all toads swallowed the bombardier beetles, 43% of the toads vomited the beetles 12-107 min after swallowing them. All the vomited beetles were still alive and active.
The page saysthe chemical spray having gone off inside the toad's own stomach
The source saysOur experiment showed that P jessoensis ejected hot chemicals inside the toads, thereby forcing the toads to vomit.
The page saysIn a laboratory study of a related species, Pheropsophus jessoensis, toads (Bufo japonicus and B. torrenticola) swallowed the beetles whole, and 43 percent of the toads vomited them back up between 12 and 107 minutes later.
The source sayswe investigated how the bombardier beetle Pheropsophus jessoensis escapes from two toad species, Bufo japonicus and B torrenticola, under laboratory conditions. ... Although all toads swallowed the bombardier beetles, 43% of the toads vomited the beetles 12-107 min after swallowing them.
The page saysEvery vomited beetle was still alive and active.
The source saysAll the vomited beetles were still alive and active.
The page saysThe beetles had fired their hot chemical spray inside the toads' stomachs, forcing them to vomit.
The source saysOur experiment showed that P jessoensis ejected hot chemicals inside the toads, thereby forcing the toads to vomit.

Source
04

Saska & Honek 2008

Saska & Honek (2008). Synchronization of a Coleopteran Parasitoid, Brachinus spp. (Coleoptera: Carabidae), and Its Host. Annals of the Entomological Society of America.

The page saysLab work showed the larvae of B. crepitans and its relative B. explodens are ectoparasitoids, insects that grow attached to the outside of a host and eventually kill it, and that they develop on the pupae of another ground beetle, Amara
The source saysLaboratory experiments have shown that larvae of ectoparasitoids Brachinus explodens Duftschmid and Brachinus crepitans (L.) (Coleoptera: Carabidae) develop on pupae of spring breeding species of the genus Amara (Coleoptera: Carabidae).Note: 'ectoparasitoids' defined in-text for the young audience; the quote carries the term for both species' larvae.
The page saysIn the field, Brachinus females lay their eggs as Amara larvae are about to pupate, and the bombardier larvae hatch just as Amara pupae become available
The source saysBrachinus adults arrived later than their hosts, and females started to oviposit when Amara larvae were just about to pupate, and Brachinus larvae hatched when Amara pupae became available.Note: The field half of the study is reported at genus scope ('Brachinus'), so the sentence says Brachinus, not B. crepitans.
The page saystags: parasitoid
The source saysLaboratory experiments have shown that larvae of ectoparasitoids Brachinus explodens Duftschmid and Brachinus crepitans (L.) (Coleoptera: Carabidae) develop on pupae of spring breeding species of the genus Amara (Coleoptera: Carabidae).Note: moved from the sea lamprey (#777), which feeds on blood and has filter-feeding larvae; the beetle's larvae develop on and kill Amara pupae.

Source
05

Ivanič Porhajašová & Babošová 2022

Ivanič Porhajašová & Babošová (2022). Impact of arable farming management on the biodiversity of Carabidae (Coleoptera). Saudi Journal of Biological Sciences.

The page saysin Slovakia, where a three-year farmland survey found it was one of the dominant ground beetles in pitfall traps
The source saysWe studied the composition of carabids in ecological and integrated farming, in three different crops in southern Slovakia. The ground beetles were caught using pitfall traps during a period of three years, from 2018 to 2020. ... Brachinus crepitans also dominated
The page saysreaching 16.47 percent of one year's catch on the organically farmed plots
The source saysThe open land species Brachinus crepitans was also dominant. Its dominant occurrence was limited to 2019 within the integrated management system (5.98%) and to 2020 in the ecological system (16.47%)Note: 16.47% is the 2020 figure for the ecological system alone, not a range across the three crops. The paper calls that same system organic elsewhere ('The crop rotation in the organic farming system was as follows', and '4 784 were in organic and 3 017 in integrated farming', which the abstract reports as ecological management). The 5.98-16.47% range the abstract prints is across farming systems and years, and the species sat at 3.12-9.84% in the other system-years, so the range is not quoted.
The page saysFarmland
The source saysThe open land species Brachinus crepitans was also dominant.Note: stats.habitat; B. crepitans dominated farmland pitfall-trap catches in this three-year study.
The page saystags: agricultural
The source saysThe open land species Brachinus crepitans was also dominant.Note: Replaces the `savanna` tag (#596), whose definition is "expansive tropical grasslands ... following migrating herbivore herds". This is three years of pitfall trapping in arable crop fields (alfalfa, winter wheat and pea) under organic and integrated farming at Nitra-Dolna Malanta, Slovakia, where B. crepitans reached 16.47 percent of one year's catch; the tag reads "Foraging across farm pastures, crop fields, and grain silos". The `woodland` tag stays on the UTEP line "Bombardier beetles of all types generally live in temperate zone woodlands or grasslands".

Source
06

University of Texas at El Paso, Centennial Museum, Chihuahuan Desert Homepage

Bombardier Beetle (Tribe: Brachini). University of Texas at El Paso, Centennial Museum, Chihuahuan Desert Homepage.

The page says4 to 15 millimeters long
The source saysThe only genus, Brachinus (described in 1983), 4-15 mm in length, contains about 40 species which occur over much of North America.Note: Genus-level figure (Brachinus), not species-specific to B. crepitans; worded at genus scope in the body.
The page saysa family whose adults tend to live several weeks
The source saysGround beetles tend to live for several weeks, during which they have ample opportunity to mate and pass on their genesNote: Stated for ground beetles (family Carabidae) generally, not Brachinus; the source's 'tend to' and 'several weeks' both kept. The only lifespan any source in the pack gives.
The page saysAt night they come out to hunt smaller insects
The source sayslike most other ground beetles, tends to come out at night to prey on smaller insects
The page saysBrachinus, like nearly all ground beetles, eats a number of insects farmers count as pests
The source saysBrachinus, like nearly all the species in the family Carabidae, is a predator, and eats a number of other insects that are agricultural pests
The page saysIt fires only when something actually makes contact
The source saysDefense Mechanism: The Beetle will only fire only when directly contacted
The page saysBeetles in the genus can also swivel the tip of the abdomen through about 270 degrees, and can spray in whatever direction a predator comes from
The source saysthe beetle can rotate the end of its abdomen 270 degrees in any direction, which allows for an impressive "firing range." In effect, the beetle can spray in whatever direction the predator comes fromNote: 270 degrees, not the 360 the pre-rewrite draft claimed; genus-level source, worded at genus scope.
The page saysGrasslands
The source saysBombardier beetles of all types generally live in temperate zone woodlands or grasslandsNote: stats.habitat; genus/tribe-wide statement. The label drops the source's 'generally', which a compressed field cannot carry, and does not strengthen it.
The page saysWoodland
The source saysBombardier beetles of all types generally live in temperate zone woodlands or grasslandsNote: stats.habitat; was 'Woodland Margins', which the source does not say: it says woodlands.
The page saysInsects, Including Agricultural Pests
The source saysBrachinus, like nearly all the species in the family Carabidae, is a predator, and eats a number of other insects that are agricultural pestsNote: stats.diet; genus-level source. The label drops 'nearly all the species in the family', which qualifies which beetles are predators, not what they eat.

Source
07

National Geographic

Bombardier beetles. National Geographic.

The page saysdangerLevel: Medium
The source sayshot enough to burn and stain human skinNote: The tier is a capability: Medium is "Can injure, but rarely seriously". A burn and a stain from a 4 to 15 mm beetle that fires only on contact is exactly that, and no cached source reports a serious human injury or a death. The page covers bombardier beetles at subfamily scope (Brachininae and Paussinae) and opens on a photo captioned "The common bombardier beetle ( Brachinus crepitans )", the same group scope as the UTEP reference already in the profile. Settled in #596.

How the table was made: a writer drafted the profile from these sources and logged each claim with its quote, a reviewer with nothing but this table checked every sentence said no more than its quote, and a script confirmed each quote appears word for word in the source. The method is in the site'sAbout page.