The larvae of the Orange Tip butterfly eat only the seedpods of their host plants (Cardamine pratensis on my patch), so they need to hatch just after the seedpod has formed. This Orange Tip egg has been laid on the foodplant at exactly the right time, just as the flower is about to open:
Hatching will take place about a week from now, by which time the embryonic seedpod will be formed. (Gestation is around 10 days, but the egg is now orange, which means it was laid 2-3 days ago.)A few insects are dependent on Buttercups, and the first local flower opened today. The larger insect in the following shot is the hoverfly Cheilosia albitarsis, which feeds as a larva on the rootstock of Creeping Buttercup. The smaller creatures are the micromoth Micropterix calthella:
The larvae of Micropterix calthella are unknown, but given the fact that they appear on the same day as the flowers open (and then stay very close to the same flowers for the next couple of months), then I'm sure there is a very tight relationship between the moth and the plant. This mating couple was photographed on the tendrils of Bush Vetch, so you can get an idea of scale:
Another Micropterix species is the wonderful Micropterix aureatella:
