I went this May to Cres and Losinj, but with few success, due to bad weather conditions.
I could see a group of three E.quatuorlineata during courtship/mating.
A fourth specimen was probably nearby, but I could only see its tail while it was escaping.
The following day, a few meters away, I could see an actual mating inside bushes, but I could take only one picture: the big female took with herself the male, which was dragged by her backwards inside the bushes.
I also have a short footage of the "group": sorry for the bad quality. https://youtu.be/tswnXCU5x9k