Taxonomic Name Changes

The latest round of changes to butterfly scientific names is being cascaded down to minor BAP players such as us. Mercifully, the name of the Monarch of the Skies Apatura iris remains unchanged. Wisely so, as that name has serious resonance and depth of meaning to many people, as it has had throughout entomological time.

Our Pledge: If taxomonists dare so much as to consider changing this sacred name the People of Purple Persuasion will rise in countless thousands, torch all centres of taxonomy and impale any taxonomists found therein, and who are not of our persuasion, on Nordic walking poles - and then cover themselves in shrimp paste outside 10 Downing Street, naked.

Meanwhile, poor Brother Quercus has been garroted again. He is no longer to be known as Zephyrus quercus but is now to be called Favonius quercus. As any humble Classicist will know, Favonius is the (pre-Christian) Roman equivalent of Zephyrus, the God of the West Wind. What, then, is the point of this name change, especially as the butterfly - which conducts its courtship and mating along sunny west-facing wood edges in early evening - loathes the west wind (which prevents it from mating)?

Meanwhile, betulae - meaning, of birches - remains the specific name of Brother Betulae, the Brown Hairstreak, which has no association with birch trees. Has anyone ever seen a Brown Hairstreak settle on a birch?

Signed, in his own blood, and with high blood pressure,
Matthew

Sallow Mildew

Photograph of a sallow spray affected by Sallow Mildew Uncinula adunca var regularis on what would otherwise have been a suitable branch (female tree of the Salix caprea type with leaves of mid-green colour, medium thickness, and a matt surface. The galls are no problem; indeed, iris eggs seem to mimic them). In several hundred hours (don't ask...) of searching I have yet to find a larva on a branch bearing anything more than the odd spot of this mildew, despite the fact that the mildew is quite common at this time of year on the shady sallows iris favours. This is remarkable, as it suggests that the females select sallows that are not going to be affected before the mildew actually starts to appear (usually from late August). Clever girls indeed... .

I have nearly finished searching the trees searched last year in Wiltshire, and it looks as if the 2010 egg lay was about 1/3rd of that of 09. More anon.

3rd Instar

Very nice early 3rd instar larva photographed in N Wiltshire on Sunday September 19th. Note his silk pad 'seat' and feeding damage either side of the leaf tip. By this stage most larvae are on their third leaf, as they move to a new leaf for the second skin change. Enjoy.

SEM Images

Thought some of you might appreciate viewing some of the SEM images of iris wing scales which I took earlier today.  Images detailing: 

Pilliform scales with inset close up of the central scale, highlighting its hollow structure.

The smooth inferior surface of a scale, laid across the textured, superior surface of pigment scales.

Close up view of a scale base.

Close up comparison of scale inferior and superior surfaces.

Enjoy!

Poxes & Diseases

Various communications have been received re iris larvae dying mysteriously, both in captivity and in the wild. Many thanks for these.

'Irisscientist' had captive 4th instar larvae die off this May in a similar manner to my recent illustrations. But Derek Smith, who has bred one or two iris in his time, wondered whether the larva I featured had been predated (I think not: I checked the skin, which seemed intact).
I suspect a wet weather virus, but welcome other people's experiences and views. I'm not an experienced breeder and don't know what I'm talking about here... .

However, in the wet June of 1977 I lost about a dozen larvae (the only year I've tried to breed more than a few) when an orange fungal rust developed on the sallow leaf undersides. I did get it checked up but have forgotten what it is called. It proved instantly fatal. It seems to be associated with wet summer weather (remember the Silver Jubilee rains of June '77?!).

In the wild, grey-white Sallow Mildew Uncinula adunca var regularis develops quite commonly in late summer / autumn on the uppersides of leaves of sallows overhung by taller trees. I suspect it is fatal to iris larvae, though the females seen incredibly adept at avoiding laying on branches / trees which later become affected by it. Does anyone have any experience of this?


Meanwhile, Gentlemen, I am in a state of Severe Nervous Anxiety: Somerset are threatening to win the County Championship... .

The Festival of Dead iris larvae

Last Sunday's outing (gentlemen, we must all Come Out...) in pursuit of iris was particularly baleful, producing just two dead 2nd instar larvae - in 2 hrs 30 mins of actual searching. My guess is that they'd succumbed during / after that very wet week at the end of August, effectively to a 'wet weather virus'. In fact, mortality in the wild so far this autumn seems to be unusually high - and that's after a very poor egg lay.

Has anyone else encountered larvae dying off like this, either in the wild or in captivity?

To end on a happier note, here's a recent picture of a healthy wild 3rd instar larva (note the pale horns, indicating recent skin change). Most have now changed into this instar.

Managing Sallows for Fun and Profit

Just how do you manage sallows in the interests of iris?

Matthew has started a discussion on the website here.

sallows

If you have experience in this area, do please share your observations.

Mr. W.A. Cope: Best authority on iris? (1954)

When referring to the egg laying numbers of iris females, on page 40 of “Notes and Views” Hyde refers to a Mr. W.A. Cope as being “one of our best authorities on this species”. As stated on page 104 of “Notes and Views” the original reference to this quote being present on page 99 (although in truth the quote is actually on pages 98 and 99) of Vol.66 of “The Entomologist’s Record” (1954). Below is a URL link to an online copy:


http://www.biodiversitylibrary.org/page/30077804#151


I write to enquire if anybody has any further information about the works of this illusive Mr. W.A. Cope, as internet searches unfortunately fail to yield any details regarding his work in relation to iris, which would deem him worthy of this title?


Any/all leads that can provide further information on this matter would be very much appreciated.


Kindest regards,



Mark

Ilia

Very nice pair of Apatura ilia clyti recently bred and photographed by Derek Smith.

There ain't no cure for love...

Latest Doings

Gentlemen, we are currently skin changing, from the 2nd to 3rd instar (in which we will stay for seven months). Note the yellow band at the back of the head, indicating that the skin is getting oh so tight... .

Searches for larvae continue, but it is quite clear that numbers are way down on this time last year - almost certainly because females were killed off prematurely by the St Swithin's Day gale. Most areas that revealed pleasing numbers of larvae last early autumn are now producing at best only one or two (yesterday I found 1 in 3 hrs 30 mins, on trees that produced 12 last Sept). However, I have found the odd hot spot, but it is very hard work.

PLEASE NOTE: This blog functions all year round. Keep visiting it, and do put your highlights from the 2010 flight season on, if you haven't already done so.