Changes in the distribution of two congener Dytiscidae over time. Occurrences of a species in steep decline, Dytiscus semisulcatus A. Before 2000 and B. After 2000. Occurrences of a morphologically similar species remaining common, Dytiscus marginalis; C. Before 2000 and D. After 2000.

 
 
  Part of: Cosandey V, Chittaro Y, Sanchez A (2024) An updated checklist of the Hydradephaga of Switzerland (Coleoptera). Alpine Entomology 8: 87-119. https://doi.org/10.3897/alpento.8.124813