I thought that it was either Noctua fimbriata or pronuba but I am really not sure of either. I didn`t see any obvious colouring to the underwing when it settled briefly on my hand but the i.d. may rest on the row of brown dowward pointing marks changing into lighter streaks. It was smaller than the Noctua species that I have seen in my garden being about 20-22mm long (w/o attenae)
I think this is either
Langmaid's yellow underwing, Noctua janthina
lesser broad-bordered yellow underwing, Noctua janthe
The differentiating characters are not visible in your photo.
Although worn, your specimen just about shows the small white marks that partly ring the stigmata of both these species. Even on a less-worn specimen, those marks can be rather indistinct (as in the photo in the last link above). You'll notice the row of black dashes in both these species.
Crystal, if you're watching, your comments would be welcome...
These are two very similar species which I read have only recently been separated. As you say, the underwing is where the truth lies. I took a long time over looking at your links and noticed that the shoulders are not at all outlined in light buff - I suppose this is due to `wear and tear`. This moth was very sleepy and probably on it`s last legs. I`m going to check the litter underneath to see if it died overnight and maybe do a p.m. When you say `stigmata` do you mean those rings that are very prominent on the forewings of other Noctua (fimbriata/pronuba) but very indistinct on this?
Loved the purplish tinge on the edges of the forewings of some of those photos.
Stigmata - yes (plural of stimga).
In principle, moths have an orbicular stigma (round) and a reniform stigma (kidney-shaped) on each forewing.
In some species these stigmata are picked-up and pronounced in the patterning; in others they are obscure.
Good luck with the p.m.!
This is fascinating!
Sorry to keep this going but are there any theories about why this is so? Perhaps it has a developmental or evolutionary significance. Any theories?
I don't know any more about moth stigmata!
There are other aspects of a moth's wing that could be pondered in the same way, eg. the venation (the veins). And here I do know a bit more... Venation is an important way to distinguish one group of insects from another. The venation of all moth wings is different to that of a wasp, say - even in those moths (the clearwings) that mimic wasps and similar insects.