Despite a cool, grey week we are hurtling towards the 2011 Purple Emperor season. Six larvae were observed in the wild in Wiltshire today. All were in the final instar. One was just about full grown (tail turning pale) and another two were extremely large. Given the week's weather forecast, it seems likely that the first pulse of the 2011 iris emergence will be pupating shortly (it may already be doing so at 'early' sites in Surrey and Sussex).
Unless late May and the first half of June are cold and wet (as happened after the wonderful spring of 2007) the Purple Emperor is going to emerge in mid June, maybe earlier. My prediction is 14th / 15th June (when I'm scheduled to suffer two days of corporate bollox). The insect usually lasts about 18 days in the pupal state in the wild.
So, if you've booked leave / accommodation for early July think again. If you've booked this for mid July cancel, you'll be too late.
Meanwhile, here is Lot's Wife, who should be full fed in 2-4 days.
And here is Joshua son of Nun who should be pupating next weekend. Both pictures were taken today.
Coming soon to a forest near you, the White Admiral...