Chalk Hill Blue aberration

[Lee Hurrell]

I know they're variable but I've never seen one like this before, seen yesterday at Denbies:

No hind wing cell spots and with silver studs

Rather helpfully posing with a normal CHB for comparison

And then a Brown Argus, the tart

Upper side was normal though

Full report and more minor variations to follow in my diary, later today.

Cheers

Lee

[lee3764]

I know they're variable but I've never seen one like this before, seen yesterday at Denbies:

IMG_5186.jpg

IMG_5167.jpg

IMG_5173.jpg

IMG_5192.jpg

Full report and more minor variations to follow in my diary, later today.

Cheers

Lee

Hi Lee,
According to my book 'A Monograph of the British Aberrations of the Chalk-Hill Blue Butterfly' (1938) by Percy Bright & H.A Leeds it is Chalkhill Blue ab.alba plate 4 figures 4 & 11.
Hope this helps Lee.
Cheers,
Lee (Cornwall).

[Lee Hurrell]

Hi Lee,

Many thanks.

I've found ab alba on the Cockayne database (http://www.nhm.ac.uk/jdsml/research-cur ... mat%3dlist) but it doesn't quiet match.

I would suggest ab. postobsoleta which is closer:

http://www.nhm.ac.uk/jdsml/research-cur ... xonID=8589

or ab. postaurantiaextensa, which is near identical

http://www.nhm.ac.uk/jdsml/research-cur ... xonID=8586

Both should be in your Bright & Leeds book, as they named them according to Cockayne, what do you think?

Cheers

Lee

[Piers]

Hi Lee,

The term "postaurantiaextensa" is referring to only one feature on the specimen shown on the Cockayne database: the ornage lunules on the margin of the hindwings. If you look at the image you will see that these are extended inwards, and and wedge-shaped. Thus the specimen is ab. postaurantiaextensa:

'post' refering to the hindwing,
'aurantia' for the orange lunules (aurum is latin for gold),
'extensa' because they are extended.

If you compare the two, you will see that your chalkhill does not have these extended orange lunules so can not be postaurantiaextensa.

Not your fault though: It is unfortunate and frustrating that the specimen illustrated in the RCK database is also missing a few spots, as this is the more obvious feature which (perfectly understandably) leads you to believe that the absense of hindwing spotting was what ab. postaurantiaextensa was all about. Naughty Caockayne Database.

Similarly ab. alba refers specifically to the ground colour of the underside; i.e. pure white (and to be ab. alba it really does have to be super-white).

For what it's worth I would go with postobsoleta (post referring to hind wing only, and obsoleta from obsoletus which essentially means 'worn out' (I think, Guy...?)

Were it to be completely deviod of spots on the hindwing (except the marginals and the central discoidal mark) it would be known as postico-obsoleta.

All t'best

Felix.

[Lee Hurrell]

Many thanks Felix for your comprehensive answer. I should remember not to take Cockayne on face value then in future!

Crikey, it really does help to know your latin then....(which I don't really, apart from the latin names for Wren and the Blackbird/Thrush genus).

Out of interest, if post refers to hind wing, what's the latin term for fore wing?
And what does postico refer to in postico-obsoleta?

Thanks again,

Lee

[Piers]

Lee,

Anti is used for the forewings.

As far as my limited (and it is really quite limited) grasp of latin is concerned postico is the same as posticum, postica, post - rear. Not to be confused with the Portuguese 'postico' meaning 'false'.

.... Guy..?? (help..!)

Felix.

[Lee Hurrell]

Thanks Felix

That reminds me of a little teaser I heard once - what comes before penultimate?

Cheers

Lee

[Piers]

Antepenultimate...???

[Lee Hurrell]

Indeed. I did sort of give it away huh...

Cheers

Lee

[Piers]

Yep. Thanks.

[Padfield]

You're all doing perfectly well with the Latin without me!

I didn't know that in zoological Latin 'anti' (not 'ante'?) and 'post' refer to the fore- and hind-wings.

'Post' can be adverb or preposition; 'posticus' is noun or adjective; but yes, they both point you backwards!

Guy

PS - For anyone who's interested, there's a superb Latin dictionary and parser available free here:

http://www.inrebus.com/assistant.php

[Piers]

'anti' (not 'ante'?)

Strangely, no. I have double checked in a few references as well. Antico (anticus?) as a prefix is also used in certain descriptive names...

But yes; anti and post for 'fore' and 'hind' (makes sense in a crude way...) antiradiata, postradiata etc. etc. usefully descriptive.

Thanks Guido.

Felix.
Ps. Your homework for tonight is to research the use of 'anti' rather than 'ante'

[lee3764]

Are you sure it's not ab. 'caeca or ab.obsoleta? Fascinating how Felix reels off these full aberration names! Me, armed with my 1938 copy of 'A Monograph of the British Aberrations of the Chalk-Hill Blue Butterfly' can only compare Lee's photo with the plates & then take an educated guess but did not know the reasons why descriptive words like anti & post were used to name the aberrations! Good stuff!
We could do with a separate thread on here for just aberrations!!
Lee.

[Lee Hurrell]

Thank you all for your help.

Felix, Lee may be right if it were to be postcaeca , depending on what caeca translates as of course...

Cheers

Lee

[Piers]

Hi hi hi...

Caeca means 'blind'.

Ab. caeca in coridon has no spots on the underside of any wings, except of course the marginal lunules (which are also blind) and the central discoidals. There is no ab. named postcaeca. Anything that could be described as this (blind hindwings) has already been named and described (ab. postico-obsoleta see above...)

Ab. obsoleta is similar to yours Lee H, but involves the forewings as well; your specimen has typically patterned forewing undersides so full obsoleta is ruled out. On your specimen only the hindwing undersides are 'obsolete'.

Hence ab. postobsoleta .

Felix.

[Pete Eeles]

Felix - you really need to write on article on the naming of aberrations so that we can all benefit from your (clearly) vast knowledge on the subject. Your recent posts have been quite enlightening. Just let me know how many beers that would require

Cheers,

- Pete

[Lee Hurrell]

Many thanks Felix.

And I would buy you a pint too!

Cheers

Lee

[Vince Massimo]

I love Chalk-Hill Blues because they are so variable. Yesterday I visited my nearest Chalk-Hill site at Colley Hill, Reigate, Surrey, where they were just emerging. I only saw 7 males, but even in that small number there were at least 2 individuals which I considered to be out of the ordinary and these kept me occupied for over 2 hours. On one the background colour of the undersides was very dark and on the other it was very pale. The uppersides of each were "normal" (or as normal as you can get with this species).

I was wondering if someone could tell me (Felix ), whether these two colourations fall within the accepted variation range for this species, or if they are true aberrations.

The middle photo is of a "normal" underside, taken a few years ago, for comparison.

Dark Male Underside

Normal Male Underside

Pale Male Underside

Cheers,
Vince

[Piers]

Hi Vince,

Chalkhill Blue undersides can vary in colour from snow white through to deep chocolate brown, slate gray, or bright orange-ochre. And that's just the males...!

There are many named underside colour forms for almost every shade...!

This may seem excessive (and to a degree it probably is), but many of these underside colour forms can be bred through in captivity from carefully selected females to produce strains with different coloured undersides implying that the underside colour is (in some instances) genetically controlled.

Felix.

[millerd]

I visited Denbies this morning (28th July) and this little chap popped up - another almost spotless under-hindwing. Considering there were many hundreds of Chalkhill Blues across the hillside, I imagine it's not surprising there have been one or two of these. I've included a normal one for comparison.

Dave