Thursday, 14 June 2012

Never hold a Black Clock in your mouth


I found a squished ground beetle on the pavement today, Pterostichus madidus, and I thought I would share with you some photos from last year of a very alive individual of this species . Curiously this carabid beetle has a curious English common name: the Black Clock. According to the book Bugs Britannica, by Marren and Mabey 'clock' was a word in widespread use to mean any big buzzing insect. As many carabids, however, this is a fast, non-flying nocturnal predatory beetle which runs to hide quickly when uncovered. This one was found under a grass tussock in the garden. Look at his sharp jaws!
 Ground beetles have glands at the end of the abdomen that produce defensive, foul tasting and caustic secretions. I must quote here an incident involving ground beetles described by Charles Darwin
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!
The pains beetle collectors went through to capture priced ground beetles! You can admire the handsome Crucifix Ground Beetle (Panagaeus cruxmajor), also known as 'Darwin's lost beetle' here. Unfortunately, due to collecting and habitat degradation, this species, formerly widespread, is now just know from three populations in the UK.
But back to my beetle, I managed to take some shots of the individual scurrying off for cover on the soil, and then I decided to capture it and give it a session in the white bowl. I think the following two photos show the pros and cons of the natural versus the white background.

Pterostichus madidus, 12 May 2012
More information
Charles Darwin letter to Leonard Jenyns in the Darwin Correspondence project.
Crucifix ground beetle (Panagaeus cruxmajor) UKBAP plan.

6 comments:

norwegica said...

I my family the name black clocks always applied to black beetles that were often found in houses (probably covering several species). You rarely see them in houses now as most have concrete flooring, rather than wooden floorboards. Though many an infestation was blamed on recently installed second-hand sofas etc.

Africa Gómez said...

Thank you for the comment norwegica, I wasn't sure the term was in use any more. I have got ground beetles in the kitchen, as they easily get in from the garden. Never heard of infestation from second hand sofas though!

allen H said...

On watching springwatch I am moved to research the term Clock.As a youngster we never used the term Beetle.The creatures we found in the garden were Clocks.Is this an Irish thing -I am in Northern Ireland or ageneral old English term?

Africa Gómez said...

Hi allen H. As far as I am aware is an old English name, but I wouldn't be surprised if it was un use in N Ireland too.

Anonymous said...

I am Norn Iron too and remember huge Clocks at my Granny's all the time

Anonymous said...

I'm from the north of England. I was a child in the early 50s and our first house was attached to a Working Men's Club. I recall how, on coming back to the house at night, on switching the light on, the entire ground floor would be (always) heaving with black clocks, which had infiltrated from the pub cellars next door. :)