Sylvie Deleurance-Glaçon and the foundations of Leptodirini biology: laboratory studies at Moulis (1957–1965)

Between 1957 and 1965, Sylvie Deleurance-Glaçon conducted one of the most comprehensive experimental investigations ever undertaken on subterranean Leptodirini at the Moulis underground laboratory in France. Through long-term laboratory breeding and behavioural observations, she obtained fundamental data on the biology of numerous species of Leptodirini. Her studies provided unique insights into population biology, longevity, activity patterns, relations to air humidity, sensory ecology, feeding behaviour, reproduction, larval development, thermal biology, species boundaries, and hybridization. This paper synthesizes the principal observations reported in Deleurance, 1963. The results reveal a remarkable diversity of developmental and reproductive strategies, including variation in larval instar number, feeding and non-feeding larval forms, prolonged longevity, extreme sensitivity to humidity, specialized reproductive biology, and evidence of physiological compatibility among morphologically distinct species. More than sixty years after these pioneering experiments, many of Deleurance’s observations remain poorly explored or have never been revisited using comparable experimental approaches. More importantly, Deleurance-Glaçon transformed the study of Leptodirini from a largely descriptive discipline into an experimental biological science. Her work therefore provided an important foundation for future studies on the biology, development, ecology, and evolution of subterranean Leptodirini.