Arno Thomaes studies the protected forest habitat types and saproxylic beetles. The research concerning the forest habitat types of the Habitats directive includes the classification, status assessment, distribution, management and threats (mainly climate change impact). Concerning the saproxylic beetles, the focal species are the European stag beetle (Lucanus cervus), cinnabar flat bark beetle (Cucujus cinnaberinus), rusty click beetle (Elater ferrugineus) and hermit beetle (Osmoderma eremita) and the research covers distribution, population structure, threats and protection, status assessment, ecology, monitoring, genetics, dispersal, morphometrics and many other aspects. Besides this, the research also covers other saproxylic beetles as well as the development of new monitoring techniques including the use of detection dogs.