They're here!

Posted by Graeme Lyons , Saturday, 23 September 2017 07:01

So I have been looking for this shield bug for the last few years but I thought it might turn up in the north of the county first. This is the nymph of the alien species Southern Green Shieldbug Nezara viridula. The nymph is strikingly different to the nymphs of the much commoner native Green Shieldbug Palomena prasina but the adults are oddly similar.

Anyway, it wasn't me who found it. I logged into iRecord to verify a few records to find a glitch in iRecord was showing huge number of already verified records as unverified. However, on the first page of these 1000 records, I could clearly see that someone had had this species new to Sussex in Rustington. Strange thing is I hadn't verified it! After a bit of digging around I realised someone was verifiying lots of shield bug records nationally from Sussex which was hindering me from being able to fulfill some of my role as county recorder. So that's stopped now and I can be a bit more linked in with people recording bugs in Sussex. The first thing I did was get the email of Dr Paul Sopp from Bob at work and headed over to see his garden of alien bug nymphs. Dr Sopp and the Garden of the Alien Bug Nymphs, sounds like a sci-fi!

So I think it's really interesting that this was first recorded by someone who doesn't usually record a lot of shield bugs. It's made a right mess of Dr Sopp's beans and it was this that first brought them to his attention when his wife commented on them. So it's only going to be a matter of time before this alien species spreads. Originally from Africa its been well established in London for over a decade now. Here are cluster of different instars. So they are clearly distinctive and eye-catching!

I was struck by how many there were, 50+ nymphs with a number of adults were reported but it's likely there were many many more than that and they have to be established elsewhere in the county, this surely can't be the only colony. If you have beans in your garden or allotment can you go out and have a look?

Here is the adult. It's a shade yellow-green than Palomena but the key feature is the front of the pronotum. It has a row of three white dots with a pair of black dots either side of these. 

And the cream leading edge to the pronotum and head are also different.

Here is a nymph feeding at the base of a bean flower, this will ultimately end up with the flower not growing and the bean failing which is what has happened to most of the crop. A big thank you to Paul for letting me see his bugs and remember to go and check your beans this week! Please submit any records via iRecord.

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