Alpine Grizzled Skipper (Pyrgus andromedae)

next page           back to list

2023 photographs highlighted in green. Click on any photograph to go to an enlarged picture, or simply scroll down the page.

22230_male_Hautes-Alpes_14Jul10 22246_male_Hautes-Alpes_14Jul10 22288_male_Hautes-Alpes_15Jul10 36166_male_Hautes-Alpes_14Jul14
   
36169_male_Hautes-Alpes_14Jul14 33458_male_Hautes-Alpes_7Jul13    

A high altitude Pyrgus, with a normal minimum altitude of 1600m, although generally found much higher. Based on my limited experience it is a rather scruffy species, the upperside ground colour being a dirty dark grey-brown with strong but rather unclear upf white marks. The upf identification keys are the three white marks in the discal region of s1/2, although these are sometimes obscure, and the oblique well-defined long discal streaks in s7, plus maybe a relatively weak cell spot.

The uph is largely unmarked, the marks being rather obscure and scruffy. The underside is similarly rather dark and untidy compared to most of its Pyrgus cousins, but similar to the Dusky Grizzled Skipper (P. cacaliae) with which it often flies, and the two can be distinguished from the others by the unh marks in s1. It also appears, from limited experience, that the uns ground colour of andromedae is a dark greyish-brown whereas the cacaliae ground colour is a much lighter, paler, brown. Whether this is generally true is unclear to me.

ref sex

observations

alt. m
22230 M

a male, matching the photograph in the Lafranchis France book, where the three upf discal marks in s1/2 are equally obscure. I am fairly confident that this andromedae.

2040
22246 M

a male, with the three upf discal marks in s1/2 are rather better defined.

2040
22288 M

I am not suggesting that 22288 is andromedae, but equally it does not seem to fit any other species, so I leave it here for comment. The strongly marked uph rules out cacaliae and probably also andromedae as I am sure this is beyond the limits of variation for these two species. Equally the weak upf marks seem to rule out everything except the Large Grizzled Skipper (P. alveus). Maybe the upf marks are just within the limits for andromedae. Occasionally a Pyrgus turns up that is rather oddly marked and does not seem to fit the template for any species. This may be one of them.

2020
36166 M a fresh male, noticeably large in the field, and with the three white upf discal marks leaving no room for doubt. 36169 is the underside. 2020
36169 M the underside of 36166. The so-called "exclamation mark" formed by the basal and discal marks in s1 are characteristic of this species. 2020
33458 M I originally had 33458 on the cacaliae page, but I am now sure that it is andromedae for several reasons: 1) the underside ground colour is very dark, and having subsequently seen a cacaliae underside for the first time, it is clear that the cacaliae unh ground colour is much lighter, 2) the basal s1 mark is elongated and pointed at both ends and, while, the cacaliae unh markings are similar, the basal s1 mark is not as elongated and pointed as 33458, 3) the discal mark in s4/5 is quite wide compared to what would be normal for cacaliae, although the distinction requires a view of a number of each in order to make such comparisons, 4) from what can just be seen of the upf marks, they are clearly too strong for cacaliae. I had it down as cacaliae originally as I was in a location where I had previously seen cacaliae but not andromedae (always risky to make such assumptions) and I had not previously clearly seen a cacaliae (or andromedae) underside, so had no real frame of reference. However, when I subsequently saw 36169, I should have made the connection. I am indebted to a French expert (who wishes to remain anonymous) for bringing this to my attention. 2040

 

22230_male_Hautes-Alpes_14Jul10

 

22246_male_Hautes-Alpes_14Jul10

 

22288_male_Hautes-Alpes_15Jul10

 

36166_male_Hautes-Alpes_14Jul14

 

36169_male_Hautes-Alpes_14Jul14

 

33458_male_Hautes-Alpes_7Jul13