Ground beetle (Carabus coriaceus) + Blister beetles

Cyberspider · Post by **Cyberspider** » Mon Oct 10, 2016 1:03 pm

Yesterday I was on a autumn walk through a little forrest near lake Rhein. After finding some Pisauridae I was hearing something. When I looked to the ground I saw a ground beetle eating on a snail. The Beetle had a body lengh of about 4-5cm.

f/8 - 1/125 - ISO 200 - tripod - natural light

click image to enlarge

f/8 - 1/125 - ISO 200 - tripod - natural light

click image to enlarge

f/10 - 1/160 - ISO 500 - tripod - natural light

click image to enlarge

I did a little clip -->>CLICK ME<<--

I hope you enjoy the pictures.

Ken Ramos · Post by **Ken Ramos** » Tue Oct 11, 2016 5:57 am

Nice set of images.

I have Blister beetles around my home and though I find them interesting, I give them their due because of the fact that the cantharidin which they secrete when annoyed can be quite painful.

Cyberspider · Post by **Cyberspider** » Wed Oct 12, 2016 4:05 am

Thank you Ken.

I found some Blister beetles in the past, too.

Meloë violaceus

and some larva (rare find)

Stenoria analis (first find in south-west Germany)

Could you show me some of your Blisters?

Ken Ramos · Post by **Ken Ramos** » Wed Oct 12, 2016 4:46 am

An interesting second set of images, especially the last two with the spotted elytra. I only have one image of a blister beetle that I see quite a few of around here, espcially late in the winter time.

If you prod at them enough you might see a dark brown liquid ooze from their joints, that is the caustic cantheridan and you don't want to come into contact with it.

Cyberspider · Post by **Cyberspider** » Wed Oct 12, 2016 9:01 am

Hi Ken,

I knew, that Blister Beetles are poisonous and that the poison comes up from their "knees". I just read about the cantheridan. I did not know, that males of some Oedemeridae have that too, to attract the females. Very interesting.

Troels · Post by **Troels** » Wed Oct 12, 2016 1:48 pm

Interesting picture of the Meloe larvae. I have frequently seen the adult females in the early spring i Denmark. But never the larvae.

The female is so fat beceause she carries around a thousand eggs she is going to burry in the soil.

The first instar of the larvae is so different from the adult that they have their own name. They are called triugulins and they immediately climb up in the vegetation and gather in flowers, like on your photo. Not beceause they want to eat there, but beceause they wait for a bee to arrive for pollen or nectar.

Their destiny is to grab hold of the fur of a bee and be carried back to the bee's nest (single living bees). Arrived to the nest the little triugulin hides in a cell and eat the nectar and pollen collected there.

Eventually it develops into a more normal looking larvae and after more moltings into a puppae. So it is in fact a nest parasite.

Troels

Ken Ramos · Post by **Ken Ramos** » Wed Oct 12, 2016 2:12 pm

Quite an interesting piece of information there Troels

That makes me wonder as to why the bees don't attack the larvae since they are acting as parasites in the nest or hive. Is it any particular species of bees or just bees in general?

Troels · Post by **Troels** » Wed Oct 12, 2016 2:58 pm

That makes me wonder as to why the bees don't attack the larvae since they are acting as parasites in the nest or hive. Is it any particular species of bees or just bees in general?

I really don't know. I am no expert in beetles. Just curious. Nature always make me wondering. I am convinced that is a good thing.

Troels

Ken Ramos · Post by **Ken Ramos** » Wed Oct 12, 2016 3:50 pm

Troels wrote:
That makes me wonder as to why the bees don't attack the larvae since they are acting as parasites in the nest or hive. Is it any particular species of bees or just bees in general?
I really don't know. I am no expert in beetles. Just curious. Nature always make me wondering. I am convinced that is a good thing.

Troels

Yes, nature indeed keeps one on their toes wondering about this and about that, pondering the evolution of life and how and where it all began. If it were not for how I was brought up, I would most surely become a Darwinist.

Cyberspider · Post by **Cyberspider** » Wed Oct 12, 2016 10:49 pm

The only parasite solitary bees. If they hang on a honey bee, they would die. The second beetle parasites only a special species of Colletes (plasterer bees).

reminder to me: do not reply by mobile phone in a train...

Ken Ramos · Post by **Ken Ramos** » Thu Oct 13, 2016 3:00 am

Cyberspider wrote:The only parasite solitary bees. If they hang on a honey bee, they would die. The second beetle parasites only a special species of Colletes (plasterer bees).

reminder to me: do not reply by mobile phone in a train...

That explains that, thanks Markus