Corfu Grizzled Skippers (Part I)

[rezamink]

Just returned from a week in Corfu and am trying to sift through my butterfly photos...

I'm getting a bit confused on the ID front! any help greatly appreciated!

I have these down as Mallow Skippers:

Mallow Skipper?

And this one as a Sgae Skipper?

What does anyone think?

[Padfield]

I think both your IDs are correct.

The question is often raised as to whether mallow skipper can have prominent white spots on the hindwing, as in your second example, but in Switzerland at least (I've never been to Corfu) it certainly does.

Guy

[Roger Gibbons]

I wonder if the second Carcharodus species might be Oriental Marbled Skipper (C. orientalis). It looks a good match according to the Lafranchis book, which says that it flies in Corfu. Just a thought. An underside shot would help, often the key in this group, although the opportunity to get an underside shot is rare with Carcharodus species.

[rezamink]

Hi Guy and Roger,

Thanks for your help with this!

I saw about 8 to 10 individuals at this site and noticed they seemed pretty variable, so I did wonder if there was more than one species?

I also saw a single individual at a site about half a mile away, but it seemed smaller and also had the hindwing spot:

Here's a pretty bad shot of the underwing which I managed to snatch!

Regards

Damian

[Padfield]

I'm always wary of identifying species from photos when I've never seen them in the field - and that includes Eastern marbled skipper (and southern marbled skipper, mentioned in another post). But all of these pictures do look well within the range of variation of mallow skipper and for my money that is the safest conclusion.

One feature I've always used in otherwise difficult cases (and which might always mislead me, of course ) is the linearity of the pd markings in s2. In mallow skipper these are always narrowly linear. In other species they are thicker and/or ill-defined. The markings on your insects are all very narrow and well defined. Eastern marbled is supposed to resemble tufted marbled quite closely, a butterfly I see a lot of in the Alps and Pyrenees. To me, your butterflies are quite typically mallow and not at all like tufted marbled.

Here is an August mallow skipper (female) from the Alps, showing very prominent white spotting:



Roger has just as much experience of Carcharodus as I do, and so it's worth taking his doubts about the ID seriously. But for myself, I don't have any real doubts.

Guy

EDIT: I just checked up my notes on that last mallow skipper and it wasn't taken in the Alps but near Lyon, when I was staying with Tim Cowles. So they can be very spotty even in France!

[rezamink]

Thanks very much for that Guy....

Very useful.

Regards

Damian

[Roger Gibbons]

The underside of rezamink’s 23 August underside looks to be alceae rather than boeticus judging from the Lafranchis book where it says that the boeticus underside spots are poorly contrasted. Mind you, the alceae underside he shows also looks rather “poorly contrasted”.

Alceae: yes, I remember now – it was Tim that had the French alceae with white spots. The location meant that it could not be Southern Marbled (C. boeticus) and was very unlikely to be Marbled (C. lavatherae) or Tufted Marbled (C. flocciferus), although Tim has discovered many new species not previously recorded in the Rhone departement (around Lyon), I don’t think he has seen any Carcharodus species there other than alceae.

I think this raises an important point, given the number of European ID queries on UKB: many species are very variable, especially in widely separated populations, and the photos/illustrations in books should not be taken as definitive. Most are simply typical. Many variants are not (and cannot be) included, else the publication would be a massive tome.

The key characteristics are much more important than “does it look like the photo in the book”. The first book to attempt ID from a characteristics perspective was the Lafranchis book, a very good start, but even this has potentially misleading information, a good example being that it states that alceae can be identified by NOT having the white spots, evidently not the case. Maybe the books should say 99% (or whatever) likely to be alceae if no white spots exist, but I guess publications are under pressure to sound authoritative. “Could be”, “might be”, probably would be edited out.

Another example is the Common Blue (Polyommatus icarus) forewing underside cell spot, a definitive indicator of icarus compared to the similar Chapman’s Blue (P. thersites) which 100% does not have the cell spot. But the converse is not always true, as icarus can be missing the cell spot as in the form icarinus or just an aberration.

And when you see phrases such as “transitional to” or “may hybridise with”, it becomes even more challenging.

I hope this is useful information. ID can be extremely difficult or sometimes just impossible – luckily butterflies themselves don’t need visual ID in order to procreate.

[Padfield]

All points well made, Roger.

For comparison, here is a spring male alceae from Switzerland, showing reasonably prominent spotting (too early in the year for any possibility of a different species), and the other two Swiss species.


(alceae)


(lavatherae)


(flocciferus)

Guy