These last days, I had the privilege to follow my friend, Frédéric Beau, Doctor in biology and specialized in the follow-up of the cistudes of Brenne.
Thanks to the studies carried out on this animal, it has been shown that cistudes regularly emerge in autumn in the Brenne. This is a relatively new fact, probably correlated to the changing conditions due to global warming.
I advise you to read Fred's memoir, available here
You can also go to the website of his association, Epimetheus.
