Search This Blog

Sunday, 13 September 2015

Now here's an odd thing.....

Saturday 12th September 2015 (Moth Night @ Cwmllwyd; Part 3). I didn't do Part 2 (Friday) due to heavy rain.

Fewer moths (only 40) and fewer species (only 20) than Thursday, but I added another three species to the list: a Drinker that bludgeoned its way into the trap at some point during the night as well as a small group of Chevrons - four counted while others absconded as I opened the trap.

So what odd thing is the old fool on about this time, then? Well, it's like this - in the trap I found the moth illustrated below and I have persuaded myself that it most closely resembles Striped Twin-spot Carpet. As always, the photo shows rather less detail than a decent hand lens and the actual insect. The twin spots on the outer edge of the forewing are absent, but then they often are if you check out photos on the internet. Dots in the central cross band are present, but barely visible in my picture. The slight inward curve of the leading edge of the forewing and the shape of the various cross lines seem an exact match with Rob Petley-Jones photo on UK Moths (please do compare and comment; this would be much appreciated). There is appropriate habitat nearby and according to Paul Waring, "In some places at low altitude there is a second generation August - early September."

Looking through my own records I found that on 14th June 2015, while messing about on the mountain, I trapped the moth shown below and named it as Grey Mountain Carpet - I now believe that the two photos shown today are of the same species and that the species is more likely to be Striped Twin-spot Carpet, rather than Grey Mountain Carpet - if you can, please set the old fool's mind to rest!

Edit 14 Sept 2015: Mystery solved! Acting on the very wise and helpful comments by Ian and Chris, I think that a firm ID can now be offered for the moth captured on Saturday. Ian's sharp eyes detected possible pectinate antennae in the top photo, while Chris suggested that there is a considerable difference in size between the two species under question. The new shot below clearly shows that Ian was spot on and I can confirm that this moth is an exact match for size for Striped Twin-spot Carpet and not Grey Mountain Carpet.

I am also of the opinion that the moth from the mountain caught in June is also of the same species and have amended my records accordingly. So now I have a new target species for next year: Grey Mountain Carpet and I can look forward to more sessions of wearily trudging up and down the mountain - I'm getting much too old for this lark!

Grateful thanks are very much due to Ian and Chris for their invaluable input into solving this conundrum.


  1. Provisional comments: Is the antennae pectinate (ie notched) in the latest specimen? - it looks VERY vaguely so in your first photo, where I think that you can see its base. Male (but not female) striped twin-spot carpets have pectinate antennae.
    Your second (older) photo has clearly not got pectinate antennae, but the wing markings look like striped twin-spot - a female of that species?
    Best to wait for more expert opinion - I mistakenly called striped twin-spot carpet grey mountain carpet once, before George spotted the pectinate antennae. Be aware too that yellow-ringed carpet also occurs in your upland patch (I`ve had them at Palycwrt, det JSB) but it`s too late for them now.

  2. Thanks very much for the insight, Ian, much appreciated. I've put the moth in the fridge - hopefully, in a few hours, I may be able to get some shots of it out of the pot; it's very flighty at present.

  3. Ian, I think your memory is playing tricks: Yellow-ringed isn't in Carms or even Wales. There are three records of Grey Mountain Carpet from Carms, and a few of Striped two spot C: the former from Mynydd Du and the latter from Mallaen. Either will be a good record!!

  4. You`re right Sam. The `yellow-ringed` I was referring to was a striped twin-spot at Palycwrt (det JSB). I should have checked my records....that`s what `early starts` do to you!
    There should be a record of striped-twin spot from Palycwrt on your database - unless it`s missing? See Newsletter No 10 Sept 2007 for various interesting records from there. It may be worth checking whether other good records from that site for the same period are in your database too.

  5. I remember now what must have inculcated the fantasy of yellow-ringed into my defective memory. When I caught the striped twin-spots at Palycwrt back in 2007, one or more seemed to have some extremely vague yellowish markings - which made me think yellow-ringed as a possibility. Jon had a look at the (live) specimens and showed me why they were actually striped twin-spots - he also took some photos, if I recall correctly.
    I`ve also had striped twin-spot at Llyn y Fan Fach (det. GT) last year.

  6. Steve, wouldn't size be of some help here, the books say that GMC is quite a lot bigger than STsC?

  7. You could well be right, Chris. I've just got it out of the fridge after 4 hours to check this and for pectinate antennae, whereupon it immediately flew off - it's back in the fridge for another 4 hours now!

    Your moth was a lot prettier than mine, though.

  8. Original post edited 11.00 Monday 14 Sept 2015.

  9. It's good that the matter is resolved, Steve. According to Sam's list, Striped TsC is an equally good record, so well done on that score!