Greenwings: Montes Universales, 30 July to 5 August 2023

[David M]

...I'm not immediately sure what the interloper at top left is.

Looks like a Chapman's Blue, Chris.

[David M]

Hi David. Correct me if I'm wrong, but I don't think named aberrations/forms can cross species. Leraut describes and illustrates an almost identical female chalkhill blue as f. tithonus (= syngrapha) but the corresponding form in caelestissimus is given as f. deliciosa, de Sagarra, 1924. Obviously, the name doesn't actually matter - she's a beautiful girl!!

I suspect the information contained in Tolman is based on the assumption that coridon is the species, with caelestissima merely being a sub-species, which was the case when that book was written over 15 years ago.

Prior to posting the image, I did a little research and found this:

...The chief argument for separation is the colour of male imagines, but, in northern Spain,
populations are often of intermediate colour (ssp. manleyi and asturiensis). A sex-
limited morph, the blue “syngrapha” female, shared by coridon and caelestissima
(Descimon, 1989) also suggests conspecificity. Disjunct distributions of the two taxa
prevent use of the cohabitation criterion...

http://onem-france.org/diane/biblio/DESCIMON_2009.pdf

[Padfield]

Hi David. Yes - I'm constantly giving that very important paper to biology teachers who persist in defining species through interbreeding and viable offspring &c.! The fact is, the taxonomic level of species is a useful but essentially artificial construct. Splitting and lumping at this level are based on subjective criteria, but from a conservation point of view, splitting is preferable, because it emphasises the unique character of many isolated, threatened populations. The chances are, this blue female is an expression of the same genetic configuration that causes tithonus or syngrapha in nominate coridon, and what we choose to call her is immaterial! She's a wonderful butterfly!

Guy