I was looking around at the various wildflowers yesterday at Cosmeston, seeing what insects might be about, when I noticed these odd growths on some of the Wild carrot flower heads. I split one open with my finger nail and a miniscule orange blob fell out; turns out that was the larva of a midge with the long-winded name of Kiefferia pericarpiicola.
The galls start off green (below left), before turning pinkish and eventually brown. According to the Nature Spot website, these galls can be seen from late summer through to autumn, after which the larvae will leave the gall and drop down to the soil to pupate. The midge only occurs in southern parts of Britain at the moment – and I only found two previous records in the Welsh biodiversity database – but perhaps that will change as our climate continues to warm and the midge flies further afield. It’s also possible, of course, that this insect is under-recorded – it seems the midge itself is almost never seen, only its gall creations.