First record of termite–fungus association in Oligocene oak wood ( Quercoxylon ) from Central Europe

The Eocene–Oligocene transition (∼33.5 Ma) brought major climatic change with lasting effects on terrestrial ecosystems. Termites are important indicators of paleoenvironmental conditions in terrestrial ecosystems, and here we report hexagonal termite coprolites (Microcarpolithes hexagonalis Vangerow) preserved within anatomically well-characterized silicified oak wood (Quercoxylon aff. helladae) from the Oligocene Menilite Formation of Central Europe. The material, recovered from Quaternary terraces of the Bečva River (Czech Republic), represents redeposited silicified wood originally derived from Menilite facies. Thin sections and micro-CT reveal termite galleries filled with coprolites, closely associated with clamp-bearing hyphae and pocket-rot features consistent with white-rot Basidiomycota, documenting a close spatial co-occurrence of termite-produced coprolites and fungal structures within a single specimen and providing new insight into decay processes in Oligocene forest ecosystems. The observed association highlights the complexity of saproxylic communities in Oligocene forests of Central Europe and is consistent with the presence of locally warm, humid (subtropical) conditions despite global cooling.