Would you identify these bugs? I live in S.W.France. Are they harmful to the lime tree that they have infested? if so, how do I get rid of them? Many thanks for your help.
I am not as familiar with French insects, but it appears you have an aggregation of Seed Bugs, Family Lygaeidae, of some sort, possibly a type of French Milkweed Bug. Seed Bugs are True Bugs and most suck juices from developing or dry seeds or the sap of grasses. They are known to form aggregations, sometimes to hibernate. My best guess is that they are not harming your lime tree, but using it as a gathering site.