miked's picture

Carabid beetle

Observed: 7th June 2009 By: miked
iSpot team
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 Carabid beetle
MG 9571
Description:

Carabid beetle which liked playing dead, the beetle was alive in both images and released unharmed after its photo session.

Identifications
Species interactions

No interactions present.

Species with which Black Clock (Pterostichus madidus) interacts

Comments

Martin Harvey's picture

Pterostichus madidus?

It looks the right shape for Pterostichus madidus, but as usual with carabids the key depends on quite small details of puncturation and hairs (on the underside) which can't be seen in the photo. I don't the species well enough to be certain, but I think there is a good chance it is the very common Pterostichus madidus.

I've occasionally seen the English name "Black Clock" applied to this beetle but I don't know the reason, if any, for that name.

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Entomologist and biological recorder

Rob Coleman's picture

I'd agree with Pterostichus madidus

This species comes in two morphs, one of which has chesnut-coloured femora (thighs!) and is easy to recognise. The other form has black legs and looks similar to a number of other black beetles, but due to the size of this one I'd guess at madidus. This is also known as 'Strawberry Beetle'

Rob Coleman

miked's picture

Why 'strawberry beetle', my

Why 'strawberry beetle', my wife is very worried it might eat our strawberries as it was found not far from the strawberry patch on the allotment. I tried to reassure her that the jaws look rather more meat eating than vegetarian.

Rob Coleman's picture

I think they are probably

I think they are probably omnivorous, so your reassurances may prove unfounded!

Rob Coleman

Martin Harvey's picture

yes, omnivorous

Rob's comment was a surprise to me, but having pursued this a bit further he is of course correct. Martin Luff has studied the diet of this species [Luff, M. L.(1974) 'Adult and larval feeding habits of Pterostichus madidus (F.) (Coleoptera: Carabidae)', Journal of Natural History, 8:4, 403-409], and concluded not only that it was omnivorous, but that on balance it could not be considered beneficial in a horticultural context, due to its mix of sometimes feeding on vegetable matter and preying on both beneficial and harmful invertebrates.

Curiously, in Luff's recent (and very good) key to carabids he states that all species in tribe Pterostichini are predatory or scavenging.

Martin

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Entomologist and biological recorder