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Small Pearl-bordered Fritillary - Favourite Photo of 2023

Week 17

The ‘Small’ theme continues this week…those dishing out the common names weren’t that imaginative were they? I mean what’s wrong with Little, Tiny, Titchy, Median, Less Than Average Sized…but no it’s Small all the way . Oh well at least these ‘Smalls’ make up for their name in appearance or character.

Please could I ask that everyone waits until a topic has been opened by me for a particular species before posting photos as then it will be easier to keep track of things? Of course our overseas members are very welcome to fill in the obvious gaps relating to rare UK migrants. As in previous years details of locations, dates, times and circumstances would be welcome as would any accompanying stories and anecdotes or other observations of behaviour and interesting other points.

Have a goodun

Wurzel

Small Pearl-bordered Fritillary

With the Bentley Wood Small Pearls now sadly gone I once again had to make the trek to Priddy Pools for my fix of this species. However they seemed to be having a lie-in this year and when Philzoid and I first visited none were found and we had to make up for their lack with Glanvilles instead. On my second visit they were all over the place. The usual spot was quite productive but the end of bank that runs parallel held crazy numbers! Whilst this was great, the warmth and the activity meant that getting underside shots was very difficult. However I eventually got lucky and one individual sat feeding for some time in a lovely position and so I was able to get my Favourite shot of the year.
Have a goodun

Wurzel

Seen an abundance of SPBF at 3 sites I visited in 2023. Glasdrum NNR on 29th May, Cambus o may on 13th June and Grantown on Spey 16th/18th June.

Best photos attached

Bert.

Like Wurzel, I encountered this species on the Mendips at Priddy Minories as a side trip from the Large Blues at Collard Hill. It was a very warm and thundery afternoon and the butterflies were very active. They had just started to settle down a little when I noticed a major bit of weather approaching from the southeast and had to abandon the exercise to avoid being caught way out in the open in a thunderstorm.I did manage a few shots though. Dave

I didn’t catch up with the first brood in 2023 but was in West Cornwall in late July and early August where there is a reliable second brood. I visited a number of sites where they seemed to be about on ok numbers. One site in particular is a lovely herb rich grassland kept free of scrub by ponies grazing it in early winter. A downside of this site is it fairly exposed and the butterflies are either sheltering in foliage or hanging on to plants being buffered by the wind. My favourites were rare exceptions photographed at this site a few weeks apart.

I took photos of this Scottish pair up at the Devil's Elbow in Glenshee on 18th June - a memorable day as I found new sites for SPBF and NBA in this beautiful but almost unrecorded area, along with mountain hares and ring ouzels. A wide angle macro shot was 2nd in the 2023 photography competition, but here also a mobile phone shot, and a close-up macro stack.

Not a species I see very often, so this heavily marked female was a nice surprise, seen in central France.
Roger

Roger Gibbons wrote: ↑Mon Feb 05, 2024 4:41 pmNot a species I see very often, so this heavily marked female was a nice surprise, seen in central France.

Wow. Thought that was a Weaver's when I first glimpsed it, Roger.

Good point, David! Have I been guilty of assuming an ID just because of where I saw it? Easy trap to fall into.

Is it selene (Small Pearl-bordered) or dia (Weaver’s/Violet)? Weighing the evidence:

I have (in Var) seen dia that look almost exactly like this one. Most look at least similar.

In Provence, dia is double-brooded in the Spring and Autumn, even at 1000m altitude, and this photo was taken in July. Maybe at high altitudes it is single-brooded.

I have been to the location in the Cévennes about seven times, in July each time. I have seen selene there on nearly every occasion (mostly males, so no confusion with dia), and not seen what could be considered dia.

The altitude is 1540m, whereas dia is almost exclusively a lowland species and I would have thought highly unlikely to occur at this altitude. But maybe I thought wrong.

The location is a “damp” spot, normally good for selene whereas in my experience, dia is a “dry” species.

I see selene in a number of locations in damp regions such as the Jura and Lozère and in many cases the females are more heavily marked, although not to the level of this one. I appears that selene is extremely variable according to location, much the same as titania.

I was not able to see the underside (it was just warming up in the weak sun) and did not see enough of the hindwing to see if it showed the angularity of dia.

The uph marginal marks look slightly sagittate (= selene, although normal for selene is highly sagittate = “pearls”) whereas for dia these marks are almost always solid (or near-solid) triangular.

Have selene and dia just become the upland and lowland forms of an original ancestor?

All in all, I find it hard to believe that it could be dia at this location, even though the look says dia 100%

Anyone (Guy?) have any experience of dia at higher altitudes?

Roger

Far be it for me to question someone with way more experience of European species than me (I've never seen a weavers Fritillary in the flesh) but that was my first reaction when I saw the picture. On closer inspection there's a few things that still make me question this butterfly, the shape of the forewings, particularly the roundedness of the leading edge, and the shape of the hindwing lunules which look quite square as in other pictures of weavers, rather than triangular that I'm used to seeing in SPBF.

Anyway, this is all said under the very large caveat already outlined and I shall now duck down behind my parapet

Sometimes experience can lead to the wrong answer because experience means that not enough thought is given.

Please feel free to question, bugboy, it's the basis of good science.

Some years ago I saw a blue at Digne-les-Bains in the Alpes-de-Haute-Provence and confidently ID’d it as Idas. I didn’t think of Reverdin’s as it seemed way too south, but in fact it was just at the most southerly tip of the distribution for Reverdin’s. If I had looked more closely there would have been no room for doubt. I was on my own, fortunately.

If I had seen the Boloria image anywhere else, I would have said dia without hesitation, as did David.

The elongated wing shape also looks good for dia.

But I would add the caveat that the Boloria species are subject to quite extreme variation, not only in terms of (strength of) markings, but also in respect of wing shape. I have images of the closely-related titania that don’t look as if they could be the same species. The geographical element is far greater in France as compared to England where there is relatively little variation within a species.

Here is a female selene from the Jura. Finally, I checked the detailed distribution maps for Languedoc-Roussillon. There were no records of dia anywhere remotely near the location, and nearly all the records were from low to medium altitudes.

I think it is recorded as an open verdict, at least until some clue comes to light.

Roger

It would be great for this to turn out to be selene, because really it doesn’t look much like one! As everyone has concluded on looks alone, this is dia every day of the week. Unfortunately until Roger heads back there I can’t see where any further clues could come from…..

I have asked the local experts, the authors of this book:
http://www.naturedugard.org/doc/2022_co ... france.pdf

I asked them – can selene look like this? – can dia fly at the Col de Finiels?

I am also aware that the thread is for favourite photo of 2023 and this is somewhat off-topic.

Roger

I don't think anyone will mind the thread going in this direction, Roger. It is, after all, related to your putative favourite SPBF image of 2023l!

Well… I have had responses from two of the local experts and both opined unequivocally that it is a female selene. The question was framed in an open way (i.e. not “do you agree that…”) and neither offered the possibility that it might be dia, which I did ask.

Given their expertise and detailed local knowledge and rigour bordering on that of Lionel Higgins, I am inclined to leave this image on the selene page.

Should I see something similar in future, I will endeavour to get an underside view as well. How often do we say on these pages that a view of both surfaces is necessary for confident ID.

If anyone is not aware of the book I referenced, it is the most exhaustive ID book I have seen, with more detailed ID clues than any other publication, covering (it seems) all forms and subspecies. It is in French, but highly visual. I was involved in contributing photos and consulted on ID clues, but I don’t have any stake in the book.

Roger

That's fine for me, Roger. You and those other esteemed identifiers are unlikely to be collectively wrong.

Roger Gibbons wrote: ↑Wed Feb 07, 2024 6:05 pm Well… I have had responses from two of the local experts and both opined unequivocally that it is a female selene. The question was framed in an open way (i.e. not “do you agree that…”) and neither offered the possibility that it might be dia, which I did ask.

Thanks Roger - did they say why they thought it was selene, given that they were unequivocal? Did they think it was aberrant or perfectly normal for the region?

Cheers,

- Pete

No specific reason cited, Pete, which maybe suggests closer to 100-0 rather than 60-40. Although I told them the location, they didn't say that, given the location, it must be xyz.

One did comment that the difference between males and females was much more marked for selene than for dia. This seems to be true, especially so for those species of Fritillary at damp, high altitudes, where the females are often heavily marked. Here is an example of a female Pearl-bordered (B. euphrosyne) from the Pyrenees at 2000m.
Roger

Wurzel wrote: ↑Sun Feb 04, 2024 6:25 pm Small Pearl-bordered Fritillary

With the Bentley Wood Small Pearls now sadly gone I once again had to make the trek to Priddy Pools for my fix of this species. However they seemed to be having a lie-in this year and when Philzoid and I first visited none were found and we had to make up for their lack with Glanvilles instead. On my second visit they were all over the place. The usual spot was quite productive but the end of bank that runs parallel held crazy numbers! Whilst this was great, the warmth and the activity meant that getting underside shots was very difficult. However I eventually got lucky and one individual sat feeding for some time in a lovely position and so I was able to get my Favourite shot of the year.

SPBF 1.1 10-06-2023a 22.JPG

Have a goodun

Wurzel

I may be misreading this, but are you saying that there were Glanvilles at Priddy last year?

To be unequivocal I guess they must be saying that either this is a very familiar look for selene, or that there is no chance that dia could be found there, or perhaps both.

I wonder what they’d have said without location info - presumably the same thing judging by the level of certainty.

If this is a familiar look for selene then to me that makes certain dia and selene effectively indistinguishable from an upperside shot alone. It’s clear that they do not see it this way though (assuming location is not the key factor), so I must be missing something - perhaps there is an indicator in there somewhere that is giving them such confidence - it would be very helpful to know what it is if so!