These really are bugs in the technical sense: they’re insects in the order Hemiptera, which are called “true bugs”, or “Chinche” in Spanish. These particular ones are pyjamas bugs (because of the stripes, I presume) Graphosoma interruptum. They’re about 12mm long.
They’re all on wild carrot, Daucus carota. Most of the plants around here are going to seed now.
I even found one pair mating. at least I think that’s what they’re doing.