is this PBF unusual?

[GOLDENORFE]

a couple people have commented how dark and heavy, thick the markings are , i had not seen this species before so cant really tell if unusuall
shot at wyre forest on sunday.
phil




and a rather special shot , so happy with this

[David M]

Unless you've 'photo-stacked' this I would say it's very unusual. The spots on the outer part of the right forewing are not at all consistent with those on the left. In fact, they're totally out of sync.

This doesn't look natural to me.

[GOLDENORFE]

hadnt noticed that part , yes it is a 2 image focus stack, will have to correct that. BUT it is the heavy block nature of the black bars and dark colour around centre of abdomen. Gill shot one same day at different location and looks completly different!

[David M]

The dark markings are more reminiscent of Small Pearl Bordered Fritillary, but irrespective of that (and the fact that the 'floating triangles' indicative of PBF ARE present) the right forewing looks like something nature cannot produce.

You take excellent photos, Goldenorfe, but is it possible for you to provide an 'unstacked' image here for closer scrutiny?

[GOLDENORFE]

i have replaced image with another one, single frame. there was a slight difference in stack at one edge.

[m_galathea]

Perfectly normal in my eyes. No two are exactly the same and so the extent of the marking is variable.

As an aside, I am not keen on the image stacking. It has made the underside shot look particularly unnatural. Just a personal observation.

[Padfield]

Melanism is relatively common in the genus Boloria. On the species page for pearl-bordered fritillary there are several aberrant, melanic individuals shown and one, Geniculata's, is very similar in pattern to yours.

I don't know if there is a special name for this form but I would describe it as within the normal range of variation, in the sense that I would expect to see a few this heavily branded in a normal year. The most extreme melanic forms I have seen have been at altitude and might be a function of the cold. It may be that such forms are commoner further north in the UK (like yours) - and perhaps this very cool spring has had an effect too.

Guy

[GOLDENORFE]

i was wondering about northern/temperature, but wyre forest not really north, the north wales specimens pete has seen in previous years are normal looking , he said he would not have recognised this as a pbf.
it is interesting though how individuals can differ

[Neil Hulme]

I agree with the others. This falls well within the range of natural variation.
Neil

[GOLDENORFE]

thanks neil

[MikeOxon]

it is a 2 image focus stack

I'm always very wary of automated processes like stacking, as it takes very careful scrutiny to ensure that the result has not become misleading.

I do sometimes manipulate images myself, usually to de-clutter a background, and have occasionally merged two images of the same butterfly, with the focus in different planes. If I do this, I use cut and paste of complete blocks, such as a whole wing, to ensure that details do not get distorted within an overall structure. There are some examples of how I have used layers in Photoshop Elements for this sort of thing on my website at http://home.btconnect.com/mike.flemming/layers.htm

I don't think I have ever done it for a posting on this site, as I know it could mislead the experts! - it's mainly to make attractive pics for my personal album.

Mike

[David M]

i have replaced image with another one, single frame. there was a slight difference in stack at one edge.

That's more like it. The wing markings are now broadly symmetrical, although I agree, for a PBF this is darker than normal, though not excessively so.

[Neil Freeman]

Going through my photos taken at the Wyre Forest yesterday, there is considerable variation in the markings of individuals.

This faded one has darker inner markings than others that I saw .

Pearl Bordered Fritillary - Wyre Forest 04.06.2012

I would love to have seen it when freshly emerged.

Cheers,

Neil F.