Iris larvae in captivity on the Glos / Wilts border and in the wild in N Wilts are now all in the 5th instar - the last two changed out of the over-wintering 4th instar this weekend. Some are now in the late 5th instar, and will change skin again very soon, but most need a few more days feeding. They are therefore a week or two behind on the last two years BUT they are quite capable of making up for lost time given the right weather - and the right weather is at last arriving...
Here's a captive one who has just cast its 4th instar skin, which it wore for some 8 months -
Re Steve C's quandary. I suspect his breeding bush came into leaf unusually early, in March, and that some larvae started feeding before the bad weather came along in early April, though other's didn't? Hence the disparity? My captive ones are kept deliberately on a late-leafing bush, so none started feeding during the nice weather in March as there was nothing for them to eat then.
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