Tags
British bugs, galls on Centranthus ruber, galls on Red valerian, leaf-roll galls, Trioza centranthi
I first noticed these strange rolled-up leaf edges about a week ago, in the lane behind my house, and, since then, I’ve seen them in several places locally.
The plant is Red valerian (Centranthus ruber) and the leaf-rolls are galls, almost certainly caused by the larvae of a little bug called Trioza centranthi. The gall is where it makes its home until it matures into an adult bug, and you can see some of the larvae in the lower right photo below.
Amazingly, I photographed the little bug (see below) on one of the plants and I think this is the adult. I’ve read that Trioza centranthi is quite uncommon and, certainly, there are only 3 records in Aderyn, the Welsh biodiversity database but I imagine this is to do with under-recording rather than rarity.
earthstar 
My Valerian covered in these galls I noticed yesterday! I live in Essex.
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Well spotted, Jenny! 🙂
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I had a look this morning and found a few rolled up edges so we have them here as well. Although many of my posts are about Dorset I actually live in south Devon!
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It would probably be worth recording them with your local biodiversity records centre or on irecord or whatever, so the progress of the insect can be tracked. 🙂
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Had a look again yesterday and found quite a few more of these. Will keep watching.
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You’re hooked now. Well done! I’m seeing more and more here too. 🙂
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Well now, until two days ago I had a lot of Red Valerian here but some over-zealous gardener has removed the whole lot! I shall wait until it regenerates (it doesn’t take long) and look for galls later on this year.
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I’m not sure if the galls are seasonal … we shall wait to hear what you discover.
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Interesting! We have a lot of red Valerian around here so I shall have to look.
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I imagine you should see them in Dorset, Philip. One of my Facebook friends tells me he’s pretty sure it’s a recent arrival in south Wales. He’s been looking out for the galls after seeing them in Cornwall a few years ago, but has only noticed them in Cardiff for the first time this year.
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