An Unfortunate Aberration


from Dennis Dell

I’m sure many members have interesting tales to tell relating to their butterfly experiences, which we would enjoy reading. I’d like to start the ball rolling with a story  which has the ring of a Shakesperian tragedy about it, with me being the King Lear or, if you like, the Hamlet of the piece!

Apatura ilia (photograph courtesy Norbert Ullman)

My story begins on 28th June 1992 in a French wood in the Alsace region, a few km away from the Swiss border near Basel. The wood was a favourite haunt of mine. Its name is L’Eichwald  [even though it is in France, the name is German, reflecting the chequered history of the Alsace; an original name, ‘The Oak Wood’, don’t you think?!].  I could always be sure of seeing several woodland Fritillaries here, as well as both Apatura iris, and Apatura ilia. Both of the latter are woodland species and can be found sharing habitats in continental Europe, whereby ilia tends to favour the more open areas in woods. Strangely, considering the very close biological relationship between these two species,  ilia’s foodplant is almost exlusively Aspen, which iris very rarely uses.
Looking at pictures in a book, there would appear to be no problem in distinguishing the two. On the wing, however, it is not always so easy. For me, if I can get a good glimpse,  I can see that ilia’s purple robes are somewhat lighter than those of iris. Also, ilia’s underside is not so well defined and is also lighter. Ilia is rarer, and I guess I did not see more than about a dozen in the 22 years I lived in that region.
It was a good Apatura day; I had seen five along the south-facing edge of the wood, and I then made my way to my favourite ride in the middle of the wood. At one particular spot [photo], the deciduous tree mixture was quite young, and the ride edges were full of desirable nectar plants, particularly Hemp Agrimony, loved by Silver-Washed Fritillaries.

I saw two Apatura here,flying above and around the young Oak trees. They were around long enough for me to realise that one, certainly, was ilia, but the other was very dark: too dark even to be iris. Even though it did not land, I was fairly convinced that it was an iole aberration, in which most of the white markings are not present; whether it was iris or ilia I could not tell.
This was the first frustration; normally I have a net with me, so that if I’m not absolutely sure what I’m seeing, I can catch it for identification purposes. I did not have my net with me on that day!  You can imagine my feelings: most of us, in a lifetime of observing butterflies  maybe get a sight of a few aberrations, but it is mainly of common species. It’s simple statistics: aberrations are rare,  and to see an aberration of a rare species such as ilia is extremely unlikely. If I’d had my net with me, I reckoned I had a good chance of netting it, because it was flying within reach around these small Oaks. There was no chance of a photo, because it did not land.  Boy, did I return home cross with myself.
I decided to return on the following day, this time with my net. This was really wishful thinking: why should this specimen stay in the same place two days running?  I supposed I hoped that it was a male, and that it would display the same territorial behaviour as male iris, although I don’t know from what I’ve read about this species, whether it behaves in this way at all. I went after work and arrived there at 4.45 [yes, I left work early!]. The Good Lord obviously was smiling down on me: a dark specimen was flying at the same spot  in aerial combat with two others !   It surely must have been the same one; a second ilia aberration one day later at the same spot would be like winning the lottery. Blow me if it did not land on an Oak well within reach; I swept it off the leaf  into my net, and could confirm at close quarters that it was indeed an iole aberration of ilia. See photo.


Now, ladies and gentlemen, what I did next many of you will disapprove of. I had a killing bottle with me and I dispatched the specimen forthwith because I wanted some photos, and I wanted to have it set. I figured that, as it was a male, it had probably already mated so that its genes had been passed on. Of course, I could not be 100% sure of this. I do not normally catch and kill, but I made an exception in this extraordinary case. I had taken this photo immediately after dispatch.
What happened during the next few months was probably a punishment from on high !
I have never learned how to set butterflies and moths properly; I can do it, but I was not prepared to risk my low skill level on this very special ‘beast’. I decided [ with hindsight, a huge mistake] to have it done professionally. The following day I took it to the local Natural History Museum, assuming, being professionals, they knew to do it straight away before rigor mortis set in. Even then, if you do leave it too long, there are methods for ‘softening’ an insect for setting.
The days went by, and I heard nothing from the museum. The days turned into weeks, and still nothing. I feared the worst…something had happened and they did not want to tell me out of shame !
Finally, early in September, I had a phone call which revealed that the worst had indeed happened. It was explained, sheepishly, that there was nobody present at the end of June [holiday time], so it could not be done immediately. It was then forgotten for some considerable time !  When they finally got round to it, they did a botch job and damaged one of the wings [my previously held mantra  that everything in Switzerland is perfect and that nobody makes mistakes there took a severe blow!]. I should have taken it to one of my several entomological friends  who would have set it immediately for me. The museum had done their best to rescue something from the mess. They eventually called in one of their expert helpers to see if he could do repair the specimen. This gentleman, the late Emmanuel de Bros, a well-known and respected entomologist in those parts, did his best to repair and set my iole. I took it away with me, and the museum, by way of compensation, also gave me from their collection a similar ilia aberration. I still have both of them. My specimen is eminently identifiable in so far as one side is perfect.

What is the moral of this story ?  If you have an important job to do, do it yourself; I should have learned to set specimens, although I still haven’t, and probably never will now. You could argue that, with modern digital photography, you don’t need to catch and kill anymore. Professionals, however, will still sometimes need the actual specimen for identification, classification, and genetic investigations.

Just for the record, my aberration was identified by their experts as iliades Mitis

on the left is my specimen, with the damaged left wing but perfect right wing; on the right is the Basel museum's ab. 'iliades mitis' [please note, the label has slipped: it should be under the Basel museum's specimen] which they gave to me;
clearly there is a difference between these two specimens, so is mine a new abberation of ilia ?
who can shed light on this?


Read more about Apatura ilia here