Not quite mazarine???

[Paul]

Last year I took ages to work out, with Guy's help, one of my Mazarines was an Osiris. Well, this year I've got this one - would it be possible for this to be a Green Underside Blue ( he says somewhat optimistically)??

[Padfield]

A mon avis, definitely mazarine!!

Guy

[Pete Eeles]

Hi Paul,

I'd go with Mazarine, I'm afraid

This is based on the miniscule number of sightings of Green-underside Blue I've had ... but the spots on the underside forewing are the size of billiard balls compared to this in my limited experience - just waiting for Guy to come along now and slap me around the head with a contradiction!

I had the reverse predicament the first time I ventured on to the continent - I so wanted a photo of a Mazarine Blue, and came back with Green-underside

Cheers,

- Pete

[Paul]

Thanks again chaps. Maybe that's another one Guy cold help me find some day!!!! PS......I think I'm beginning to hallucinate!!

[Padfield]

With pleasure! But alexis is an early one. In a normal year it can be guaranteed in the Rhône Valley from April till June. I have seen it into July at higher altitudes but it's single brooded - the same sort of time-scale as green hairstreak, for example.



Guy

[Roger Gibbons]

Green-underside Blue (glaucopsyche alexis) is very much a spring butterfly. I used to spend holidays in France in July and never saw it except for one holiday to the Pyrenees in May, so I concluded then that it was localised. But having spent the last three summers in France, I find it is actually very widespread and often quite common but has all but disappeared in lowland areas by the end of May. It is also very variable: in terms of size where some specimens can be very small, in terms of the colouring in which the basal flush can vary from blue to green (here’s a pic 9700 of a mating pair I took in mid-April), and quite significantly in terms of the uns spots which can be non-existent on the hw and much reduced on the fw (Guy doesn’t buy that my mystery blue was alexis, though).

glaucopsyche alexis_9700.JPG (169.73 KiB) Viewed 1014 times

The alexis male is quite a bright blue, and can easily be identified by the black border which is characteristically wider at the fw apex.

The really tricky species is the closely-related Black-eyed Blue (glaucopsyche melanops), very similar, but gone by the end of April, I find (in Var). I saw one for the first time last year but saw several this year in different localities. It’s so similar to alexis that a close look is needed.

Mazarine, I find, is encountered much more frequently at altitude. I have found it in low-lying areas, but mostly at 800m+ and often at 2000m+. It seems most common from mid-June onward to me. It’s quite noticeably dark in flight, so not difficult to ID even in flight. Here’s a pic taken in the Valais at over 2000m last week (13323) – easy to pick out the three Mazarines!

blues_group_13323.JPG (217.66 KiB) Viewed 1014 times

[Padfield]

Nice piccie!

I can see plenty of idas blues, little blues, Grisons frits and two eros blues. There's just one blue (left of the two upper right mazarines) that leaves me in some doubt. It actually looks more like a silver-stud. But gathering with idas?

Guy

[Padfield]

Oh - and that looks very like a female glandon blue lurking in the top left-hand corner...

Guy

[Roger Gibbons]

I've blown up the original photo and I think the blue is Eros - it looked very much like others that I know were Eros for sure, and there were a few of them around (it was at Mattmark). I didn't see any Silver Studded there. I think the brown one was Small/Little - I blew up the original and there were no discal or marginal marks. I've never actually seen a female Glandon (I suppose they must exist!) but Tol & Lew shows the same discal marks as the male.

[Padfield]

The blue in the middle is eros, and the one next to the little blue (underside view) is too. But the one I mean, near to the two mazarines definitely isn't eros...

Female glandon can have a very inconspicuous spot on the upf. Your butterfly seems to have slightly chequered margins, but it's not easy to tell in the big picture.

This is female glandon (taken with the video camera, before I got a digital camera):



Guy

[Padfield]

Here's my diagnosis of all those blues. Do you agree?



(M for mazarine, I for idas, E for eros, L for little and ? for the two I'm not sure about).

I just LOVE sorting out groups of blues like this!!

Guy

[Paul]

I am in awe!

[Roger Gibbons]

You can have the advantage of seeing the blow-ups!

I think the fringes are just worn, rather than chequered.

blues_group_13323_minimus400.JPG (120.3 KiB) Viewed 934 times

The deeper blue may well just be the camera angle. The marginal markings look Eros to me, based on my experience of only seeing this species maybe 12 times. The hw border does look heavier than you would expect for Eros (and I agree it does look decidedly Silver-studded), but the black spots look Eros-ish and the slight extension of the black margins along the veins matches what I was seeing on other known Eros. I spent most of four days at this site and didn't see any Silver-studded.

blues_group_13323_eros400.JPG (103.41 KiB) Viewed 934 times

and, for comparison, an Eros that I am fairly sure is that:

polyommatus eros_13262_400.JPG (114.93 KiB) Viewed 935 times

I also have a blues group shot that includes Alpine and Glandon Blues. It was quite a good way to spend a morning!

The highlight was this female Alpine Blue (albulina orbitulus) with terrific blue dusted cell spots:

albulina orbitulus_13379.JPG (173.99 KiB) Viewed 934 times

[Padfield]

Thanks, Roger!

Yup, that's a worn minimus! It looks quite different in close-up. However, I am quite certain the blue you label blues_group_13323_eros400.JPG is not eros. This is a butterfly I have masses of experience of and feel very confident with - it's a local species for me. Above all, it is identifiable readily even in flight by the shade of blue and at rest by the overall appearance and jizz. I cannot make that blue into eros no matter how hard I try!! Wrong colour, wrong shape, wrong markings, wrong jizz. By contrast, I would instantly identify polyommatus eros_13262_400.JPG as eros.

The black spots are typical for silver-studded blue, in Switzerland, anyway, as are the black lines coming in from the edges:



I've never seen silver-studded blue at Mattmark either, but (humbly, as ever - and I really mean that!!) I do think that is what it is. The extent of the shading on the uph probably excludes idas and the general appearance is not idas. I've seen small mazarine blues that look essentially like that but my gut tells me this is not mazarine.

Interestingly, this year I have found idas and silver-studded flying together for the first time in several places. I used to think there was only one species at each site but that proves not to be the case.

I guess we'll never know! But it's fun analysing...

Guy

[Roger Gibbons]

I'll have a good look through all the photos of that trip and see if I can find anything that throws more light on it.

As you're in analysis mode, I was in the process of studying these photos for possible Darwin's Heath (coenonympha darwiniana) (I've got to see one someday?) and have been analysing the ID pointers on your and Matt's sites. These four pics (or at least three, as 7613 looks somewhat Pearly) seem to fit quite well for darwiniana on most, if not all, points. As you've seen them frequently, you might be able to offer an opinion. They just don't look like Alpine Heaths (coenonympha gardetta) to me. I have many photos of gardetta and they seem quite clearly different.
http://www.butterfliesoffrance.com/darwiniana.htm

[Padfield]

Ah! Very interesting!!

I agree - your first one looks like arcania. The others would appear to be form philedarwiniana, which I believe flies at Mattmark. Is that where they were photographed?

This is a pure darwiniana, photographed this year:



The highest spot on the hindwing is inside the white band (distinguishing this from arcania), the black spots are golden-ringed and the underside of the apex of the forewing is essentially golden, not whitish/greyish.

This is pure gardetta, photographed just the other day:



Your insects look somewhere between the two, and this is likely to be what they are!! The apex looks more like gardetta and the unh more like darwiniana .

I quote from the Swiss 'Bible' (Les papillons de jour de Suisse et leurs biotopes, by the Ligue Suisse pour la protection de la nature):

'On trouve des populations visiblement mixtes pratiquement partout dans les vallées méridionales où C. gardetta et C. darwiniana se rencontrent, ainsi que dans le Haut-Valais, dans les vallées des Alpes uranaises et au Nord des cols du San Bernandino, de la Bernina et d'Il Fuorn. Ces formes de transition, désignées par f. philedarwiniana et visiblement hybrides, ont souvent été confondues avec C. darwiniana et parfois avec C. arcania. Leur distribution doit encore être étudiée plus à fond.'

There you have it!

[Roger Gibbons]

7613 was from Isola 2000, 12178 and 12194 from the Col de Vars, and 13427 from Mattmark. All locations over 200m. Pure gardetta were flying in good numbers at both sites at the same time.

If their respective distributions must be studied more deeply, I look forward to the conclusions.

I suppose this is half a life-tick?

Thanks for the analysis, Guy.

Next I'll have a good look at my pales/napaea photos from Mattmark. I did get to see mnestra there.

[Padfield]

According to Kudrna there is a narrow hybrid zone between all three species, and he mentions as specific sites Lago Maggiore and Col de Larche. Now I'm not quite sure, but I think both Isola 2000 and Col de Vars are somewhere near the Franco-Italian border, not so far from Col de Larche...

Guy

[Roger Gibbons]

Yes, the Col de Vars and Isola 2000 (locations over 2000m, not 200m as per my earlier post) are in the same “corridor” as the Col de Larche. I visited the Col de Larche in the second week of July both last year and this year – last year the temperature was 12C and a biting cold wind so only a few Geranium Argus and a single Large Blue flying there, and this year 13C and a torrential downpour most of the day, so I stopped off in the town of Larche to get a hot coffee to warm myself up. How anything lives there if this weather is typical…