Bombardier beetles

[paul m]

This is a bombardier beetle that I found in grassland near Dol, Brittany - they're quite rare in UK. It's a small ground beetle which has the ability, when attacked, to release a stream of chemicals from its rear which ignite and explode!

There are several species - does anyone see them regularly? Brachinus crepitans is the most common in UK.



Better picture at:

http://bugguide.net/images/cache/5QV...2KQK2KEQNK.jpg

[Guy F]

I've never seen one personally, they sound very interesting. Have you ever seen one 'blast' anything?
Guy

[paul m]

No, indeed, I've hardly ever seen the beetle .... I have seen it on film. I'm told that they used to be common in some places in London - if you didn't se them you could hear them cracking at night ....

Originally Posted by Guy F

I've never seen one personally, they sound very interesting. Have you ever seen one 'blast' anything?
Guy

[goosey]

Originally Posted by paul m

This is a bombardier beetle that I found in grassland near Dol, Brittany - they're quite rare in UK. It's a small ground beetle which has the ability, when attacked, to release a stream of chemicals from its rear which ignite and explode!

Fantastic! I have never heard of, or seen them (I think, but they look familar). I have just had a quick google it says they are ground beetles Carabidae, but I can't see a latin name, but if there are over 500 species, that's alot of Latin names to devise!

[pgmoni]

Hello
If you look up Brachynus crepitans, you'll find what you are after...
Cheers
Philippe

[paul m]

Welcome Philippe. Nice to have some Belgian insect expertise here!

Originally Posted by pgmoni

Hello
If you look up Brachynus crepitans, you'll find what you are after...
Cheers
Philippe

[pgmoni]

Thanks for the word of welcome Paul.
Belgian it is, but I am not too sure about the expertise part !!

Philippe

[goosey]

Originally Posted by pgmoni

Hello
If you look up Brachynus crepitans, you'll find what you are after...
Cheers
Philippe

Thanks Phillipe, that's what I wanted. Good to have you with us! Welcome .

[goosey]

Philippe - a cheeky question, but are you the same Philippe that has the INSECTES11bisbis Webite? If you are, David Jones from My Bit of the Planet passed me your link back in May. A fantastic amount of work and information has gone into it - you should be really proud of it. If you are not the same Philippe, sorry, there are probably a lot of Philippes in Belgium . Have a look it is excellent!
I don't have any knowledge of French but manage with the Latin names to put in to English - thank goodness for Linnaeus!

[H Dogg]

The correct spelling for the Bombardier Beetle is as paul say's Brachinus crepitans. Unless it has changed very recently, which i arnt aware of. Although it seem's to have a y not an i in Brachinus in some non UK text although its the same species. Quite strange.

[paul m]

Yes, Brachynus is the old term for British usage. I would normally check the latest nomenclature at - The Coleopterist - but the site is down at the moment.

There are other Brachinus spp in Europe although rare in Britain. Oddly enough they tend to be found (in UK) on "wasteland". Recently the sister species B. sclopeta was found in London on a site doomed for development and attempts were made to transfer it to a nearby 'safe' site:
Beetle could become Britain's first extinction of new millennium - Independent Online Edition > Nature

Originally Posted by H Dogg

The correct spelling for the Bombardier Beetle is as paul say's Brachinus crepitans. Unless it has changed very recently, which i arnt aware of. Although it seem's to have a y not an i in Brachinus in some non UK text although its the same species. Quite strange.

[pgmoni]

Originally Posted by goosey

Philippe - a cheeky question, but are you the same Philippe that has the INSECTES11bisbis Webite? If you are, David Jones from My Bit of the Planet passed me your link back in May. A fantastic amount of work and information has gone into it - you should be really proud of it. If you are not the same Philippe, sorry, there are probably a lot of Philippes in Belgium . Have a look it is excellent!
I don't have any knowledge of French but manage with the Latin names to put in to English - thank goodness for Linnaeus!

Hi Goosey
the short answer to that is NO ! but there must be some confusion somewhere, because the site you link to is by ALAIN Ramel (and he is French), not any Philippe that I know of. It is indeed extraordinarily well documented, and a great reference site.
Now, David Jones has indeed a link to my own site
Macrophotographie d'insectes de France et de Belgique
which is definitely a smaller affair, just pictures with little info actually.

So in the end, it seems that I might or might not be the Philippe you mention

Cheers
Philippe

[pgmoni]

Originally Posted by H Dogg

The correct spelling for the Bombardier Beetle is as paul say's Brachinus crepitans. Unless it has changed very recently, which i arnt aware of. Although it seem's to have a y not an i in Brachinus in some non UK text although its the same species. Quite strange.

I believe you are right that this is now the accepted spelling. Brachynus is probably the obsolete version, as it is the "correct" one etymologically : the Y here stands for a greak Upsilon, which would naturally translate into Y (interestingly we call Y "greak I " in French - I grec). Probably in the same vein as deciding that all genus names ending with a are feminine - which is horrendous for a purist (which I am not, but...) and leads to confusion all over the place except perhaps in academic circles. On the web, you 'll find Eurydema ornatus, ornata (the correct one nowadays) and ornatum (used to be the correct one) Oh well...
Philippe

[paul m]

I think this is an area I don't want to get involved with! The combination of 'correct' Latin and scientific nomenclature is scary.

Yes, on the point you make, there tends to be the assumption that 1st declension -us, -a, -um endings are masculine, feminine and neuter respectively therefore the adjective (the species name) should agree with them. Fails to take into account that some fourth (fifth? I forget) declension nouns are derived from the Greek and therefore, as you point out, an -a ending can be masculine or neuter ....

One area where there is a discrepancy between British and other usage is with the number four. As I recall the correct Latin is quatuor whereas most British entomological spelling goes for quattuor - as in Propylea quattuordecimpunctata.

So I just go by the printed species lists although there are older entomologists who will argue all day about the 'correctness' of a spelling!

Originally Posted by pgmoni

I believe you are right that this is now the accepted spelling. Brachynus is probably the obsolete version, as it is the "correct" one etymologically : the Y here stands for a greak Upsilon, which would naturally translate into Y (interestingly we call Y "greak I " in French - I grec). Probably in the same vein as deciding that all genus names ending with a are feminine - which is horrendous for a purist (which I am not, but...) and leads to confusion all over the place except perhaps in academic circles. On the web, you 'll find Eurydema ornatus, ornata (the correct one nowadays) and ornatum (used to be the correct one) Oh well...
Philippe

[goosey]

Originally Posted by pgmoni

Hi Goosey
the short answer to that is NO ! but there must be some confusion somewhere, because the site you link to is by ALAIN Ramel (and he is French), not any Philippe that I know of. It is indeed extraordinarily well documented, and a great reference site.
Now, David Jones has indeed a link to my own site
Macrophotographie d'insectes de France et de Belgique
which is definitely a smaller affair, just pictures with little info actually.

So in the end, it seems that I might or might not be the Philippe you mention

Cheers
Philippe

So sorry Philippe! You are exactly the person I thought you were and I do have your link from David, but I copied and pasted the wrong one from my favourites - I am not usually so dippy, just over excited about spotting the connection. I do love your site and photos and the praise was intended for you.

[Guy F]

What would happen if one of these beetles sprayed it's chemicals on a human? I think I've read before that they can give us blisters?
They sound very interesting, and I think it would be great to see on in action!
Guy

[paul m]

Originally Posted by Guy F

What would happen if one of these beetles sprayed it's chemicals on a human? I think I've read before that they can give us blisters?
They sound very interesting, and I think it would be great to see on in action!
Guy

I refer you to Charles Darwin :
Brachinus. Explosion very loud and visible; the skin of my finger, was for many days afterwards stained brown; at the instant of explosion a sensation of warmth was felt; taste of secretion very acrid, even when diluted. June.

COLEOPTERA, Carabidae: Brachinus maculipes Waterhouse, G. R. (1841a: 351), one in the BM (186344), Maldonado. B. nigripes Waterhouse, G. R. (1841a: 352), two in the BM (186344), Maldonado. B. platensis Waterhouse, G. R. (1841a: 351), (=B. vicinus Dejean), four in the BM

Smith, K.G.V. 1987. Darwin's insects: Charles Darwin's entomological notes, with an introduction and comments by Kenneth G. V. Smith. Bulletin of the British Museum (Natural History) Historical Series. Vol. 14(1): 1-143.

[Guy F]

Thanks for that information Paul, they don't sound too scary then (for us humans anyway!). Am I really reading it right that Darwin tasted the secretion? If so then that's dedication
Guy

[paul m]

Oh yes. Not untypical of the times and earlier - people used all their senses when investigating something new! Less of a problem for entomologists ... sometimes fatal for botanists. In earlier times you can read peoples' descriptions of the effects of tasting a new plant - mouths going numb and being unable to speak, severe vomiting, unconsciousness, &c &c.

Well, you live and learn .... or, if you don't live, someone else learns!

Originally Posted by Guy F

Thanks for that information Paul, they don't sound too scary then (for us humans anyway!). Am I really reading it right that Darwin tasted the secretion? If so then that's dedication
Guy

[paul m]

I've been reading up more on these because 'bombing' seems to have evolved twice amongst beetles: the Paussinae ("flanged bombardiers") are a much older group than the Carabidae.

While looking this up I came by references to Anthiini which don't cause explosions but do squirt the same chemicals considerable distances with some accuracy. In Afrikaans they are called oogpisters. http://upload.wikimedia.org/wikipedi...sexguttata.jpg

They are fascinating, themselves, but have, apparently stimulated the evolution of a reptile mimicking a beetle - a very uncommon occurrence. The young Heliobolus lugubris lizard mimics the beetle:
CapeSnakes

[paul m]

There's another quote from Darwin in Wikipedia:

"A Cychrus rostratus once squirted into my eye & gave me extreme pain; & I must tell you what happened to me on the banks of the Cam in my early entomological days; under a piece of bark I found two carabi (I forget which) & caught one in each hand, when lo & behold I saw a sacred Panagæus crux major; I could not bear to give up either of my Carabi, & to lose Panagæus was out of the question, so that in despair I gently seized one of the carabi between my teeth, when to my unspeakable disgust & pain the little inconsiderate beast squirted his acid down my throat & I lost both Carabi & Panagæus!"

A sidelight: C. rostratus is regarded now as probably not a British species or extinct and P. crux-major is very rare.

Originally Posted by Guy F

What would happen if one of these beetles sprayed it's chemicals on a human? I think I've read before that they can give us blisters?
They sound very interesting, and I think it would be great to see on in action!
Guy