Henri Descimon is one of the world's experts on European butterflies. In his later years he increasingly concentrated on Asian montane butterflies.

Here he meets with Michael C. Singer in an unidentified coniferous woodland in the South of France. (Photo courtesy of Camille Parmesan and Mike Singer)

RIP: My good friend Henri died in Marseille on 1 January 2025. I will miss his enthusiasm for and deep knowledge of butterflies, species, and evolutionary genetics. And his sense of humour. He used wonderful words in his scientific publications, such as "cohabitation", meaning sympatry (this word echoed the newspaper term used for President Mitterrand's living in with his mistress), and "mixiology," meaning hybridization studies.

Henri died at 90, the same age as Alfred Russel Wallace when he died. I hope to live that long, and aspire to live that productively, too!