Cydia interscindana – New for VC22 and 14th UK record, 14/09/2020

In general I’m not often allowed to trap on ‘school nights’ but thankfully the night of 14-15^th September 2020 was an exception. It was going to be a warm night with favourable winds, so I could put the trap out with the promise that I’d sort through it after school the next day. In hindsight the next night turned out to be far better conditions for trapping, with many Berkshire moth’ers getting several hundred moths, incredible numbers for the time of year. But I’m very glad I picked the night I did.

At about 21:30 on the Monday evening I went out to check the trap one last time before leaving it alone until the morning. There weren’t huge numbers but Orange Sallow was a nice lifer and there were several other more common things. The only other moth that caught my interest, however, was a very small tortrix sitting on the rim of the trap. I knew that I hadn’t seen it before, so very carefully I potted it up and took it inside to examine.

Being very poor at tortrix identification in most cases, the first thing I did was to take some macro shots of the moth. Thankfully it sat still for long enough to get some decent images, although a few times it did fly a short distance only to be recaptured – I may have been slightly more careful had a known what it was! I next had a look through the tortrix section of the Bloomsbury Field Guide to the Micro Moths of Great Britain and Ireland. I generally don’t have much success when attempting to ID tortrixes in this way, but I couldn’t find anything that looked spot on this time. It looked quite a lot like Grapholita jungiella but flight season was off.

Being none the wiser to its actual identity, I then posted an image of the moth along with my very tentative ID on a young moth’ers WhatsApp group, and also sent them to Sean Foote (@mothIDUK) on Twitter. Sean got back very quickly as always, saying it looked odd but he couldn’t see what else it could be. Still not convinced, I then posted images in the UK Micro Moth Identification Facebook group. This time I was met with success, as Ben Sale quickly commented to say it was not G. jungiella, but the far rarer Cydia interscindana!

I got straight onto the laptop, and started researching the species. The first thing I checked was the Berkshire micro moths spreadsheet, and quickly realised that my moth wasn’t present, so was new for VC22. I next tried ukmoths.org.uk and britishlepidoptera.weebly.com, my go-to websites for moths, only to find it wasn’t present on either of them either! Indeed, the only reference I could find to the species’ presence in the UK was Robin Peter Knill-Jones’s detailed report on his Bucks record from late August 2019, the 6^th British record at the time (see https://www.researchgate.net/publication/338855501_The_sixth_British_and_first_Buckinghamshire_record_of_Cydia_interscindana_Moschler_1866_with_suggestions_to_assist_in_mapping_its_UK_distribution).

Since my initial research I have found out a little more about C. interscindana. It is a species that feeds on Juniper (Juniperus spp.), and was first recorded in the UK in 2016. To the best of my knowledge my record was around the 10^th for the UK, following 4 from the Denham area of London, suggesting there is an established population in the area, 1 Surrey record not too far from the London ones, Robin’s Bucks record, and a few from Middlesex this summer. No doubt I have missed some, but it is clearly a very rare and localised species. What is remarkable though is, through a quick Twitter search, I discovered that there were in fact 2 further records from the same night as mine – one in an unknown location and one from Worcestershire; easily the most isolated of the British records. So, despite this moth not being in many (any?) of the UK moth field guides or websites at the time of writing, this is clearly a species rapidly expanding its range across the UK, and should definitely be on all our radars in the future.