I found a Western Conifer Seed Bug in the garden a few days ago. It was probably attracted in by the light on the moth trap. It took me a while to work out what it was. The obvious first thought was Shield Bug but I didn't recognise it and at a good two centimeters, it was too big for the usual candidates. Fortunately the white diamond pattern on its back was distinctive and a quick search on the web came up with the answer.
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| Western Conifer Seed Bug - Leptoglossus occidentalis |
The bug is a native of North America . It became established in Europe in the 1990s and eventually spread to the UK in 2007 where it has now become established. It feeds on sap in conifer trees but does not appear to do any permanent damage, although it could become a pest in conifer nurseries.
It is actually a Squash Bug from the family Coreidae rather than a Shield Bug which is the family Pentatomidae.
Finding it reminded me that I have seen a few other Shield Bugs over the past couple of months. This fifth instar Common Green Shield Bug gave the opportunity of a chocolate box picture rather than the usual record shot. Just lucky with the lighting on this occasion.
This should not be confused with the similar looking Southern Green Shield Bug, which is another recent arrival from the continent. Whilst the Common is a sap sucker living on a variety of plants and not doing any real damage, the Southern is more of a threat to bean and fruit crops. It remains to be seen if it becomes established enough to be recognised as a pest.
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| Common Green Shield Bug 5th Instar - Palomena prasina |
I have yet to find a Southern Green but here is an old picture of the Common Green adult stage. In the Southern the tail end dark patch is a pale green/grey colour and there is a straight row of five dots across its back, three white and two black.
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| Common Green Shield Bug Adult - Palomena prasina |
The next up is a Hairy Shield Bug, sometimes called a Sloe Shield Bug, well camouflaged on this thistle head. This one found whilst we were out looking for Brown Hairstreaks at the Steyning Rifle Range
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| Hairy Shield Bug - Dolycoris baccarum |
And a Hawthorn Shield Bug which as the name suggests feeds on haws. This one again attracted to the light from the moth trap.
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| Hawthorn Shield Bug - Acanthosoma haemorrhoidale |
These Shield Bugs are also known as Stink Bugs due to their ability to release a fowl smelling fluid when threatened. It doesn't sound very pleasant but to date I haven't manged to provoke one of them enough to cause them to deploy this tactic against me.
It was good to find the Western Conifer Seed Bug as it is relatively new to this country but I am still missing a good few of the longer established species. I will have to put a bit more effort into this next year.
